Armor best setup

[MadImmortalMan]

Never underestimate the value of being able to throw 25 divisions behind your enemy's lines that he cant catch up to.

Yeah, pretty much. Last night I destroyed most of the UK's military force as Italy with 5 divisions of 1 L Arm, 1 Mot. They had amphib landed in Portugal (Spain and Portugal in the Axis), and gotten nearly as far as Madrid before my infantry from the former French line could get there to stop them. Once they got bogged down on that, I shipped in a corps of light tanks from Africa and sent them on a mad dash to Gibraltar. Then up the coast to Lisbon and La Coruna. 70% of the standing British military was on the Iberian at the time, and I strangled them to death.

You can spam out those 1 mot 1 larm units like crazy too.


25 divisions would completely waste the Soviets probably.

 

[Exterous]

Man, I would think 4 and 5 line brigade divisions would add alot of frontage/supply and fuel usage in exchange for less flexibility - less front coverage.

I rarely do anything other than 2x Line Brigade + 2x Support Brigade for my Armored forces - but then the past game I had had a front with Russia spanning from Murmansk all they way through what remained of Turkey. (So # of divisions was way more important)

I have found in all occasions so far that this combination is more than enough for my needs. I have made some 3x line brigades but always found that they were way more power than needed. Having a couple more smaller divisions allows me to, IMO, be more fluid and flexible - but I also always use Airpower and multi provice attacks when possible

2x MArm
2x SP Arty
-or-
2xMArm
1x SP Arty
1x Eng
Is the way to go

 

[pnt]

Well,
2 Arm + 2 SP Art gives you a softness of 45% and a max frontage of 10.
3 Arm + 2 SP Art gives you a softness of 40% and a max frontage of 12.
I would recommend the latter. Same goes for your L.Arm/AC division.

For those of you who like AC, why not try

3 Arm + 1 AC (34% soft, speed up to 9), and
3 L. Arm + SP R Art (40% soft, speed up to 11).

This way you skip Mot, Mec, and Art (lots of techs is you go through them, including doctrines). Could in fact be the most effective overall force composition.

I'm sure the numbers add up, but any country that can afford to spam so much armour at the expense of motorised / leg infantry is surely wallowing in game-breaking amounts of IC......

Still, IC spamming is optional

Actually, L.Arm is cheaper and has lower supply consumption than Mec. So the
3 L.Arm + 1 SP R Art
division is not only the fastest, but also one of the cheapest hard divisions you can get. L.Arm has fewer attacks than Mec, but compensates for it by its better hardness, providing double the protection against Inf.

As for
3 Arm + 1 AC,
it is cheaper and requires less supplies than 3 Arm + 1 Mot. It is a fast and very powerful division. You would build them in multiples of 4, and use each group with a Corps HQ for breakthroughs.

See costs at http://www.paradoxian.org/hoi3wiki/Land_units

 

[pnt]

One combo I havent seen on here is:
L Arm x 2
AC x 2

The problem here is that you have a quite high softness (53%), and your AC maxes out it speed at 9.9, while the L.Arm goes up to 11. Thus, you will eventually have to rebuild these divisions. Also, divisions with 2 combat brigades max out their frontage at 10 rather than 12, and so are not the best choice for breakthroughs.

 

[DredMorte]

Best combo is:

Armour
Armour
Armour
Armour
Motorized

8 speed, 33% Softness (Combined Arms Bonus), lots of dmg, very tough.

Only weakness is supply.

 

[pnt]

Well,
2 Arm + 2 SP Art gives you a softness of 45% and a max frontage of 10.
3 Arm + 2 SP Art
gives you a softness of 40% and a max frontage of 12.
I would recommend the latter. Same goes for your L.Arm/AC division.

It seems to me from playing that support units take less damage in combat than front line, which is why I go for these two sets. In HOI2 my Arm/Mot groups were always waiting for the MOT component to repair and rest (improve ORG). So by sticking with this combo, I do not even upgrade my AC, but as I upgrade the ENG, they get crazy good at crossing rivers to the point that I can ignore taht feature on maps, and forts also cease to exist...So i do not consider the Eng to be not "proactive" as you say.

Eng has the drawback of maxing out its speed at 8, which is slower than both Arm (9) and L.Arm (11). Also, it has a very high softness (95%), low combat stats, and requires many additional techs. Only a 4 Arm + 1 Eng combo (35% soft) is a reasonably good, but mainly in rather particular circumstances.

You are right about the damage to combat brigades, but it is the same no matter how many you have. Thus, to minimize the damage to each you want to have a full set of 12 on the front line.

The most powerful armored division is thus
3 Arm + 2 SP Art. (40% soft, speed up to 9)
The thing here is that it only goes really well with
2 L.Arm + 1 Mec (43% soft, speed up to 10.4)
for exploitation, but the speed difference is very small, and the latter are quite weak. If you use them however, this is probably the most powerful overall combination.

 

[pnt]

Best combo is:

Armour
Armour
Armour
Armour
Motorized

8 speed, 33% Softness (Combined Arms Bonus), lots of dmg, very tough.

Only weakness is supply.

Actually, in 1947 the softness is only 32.6%, so probably does not qualify for combined arms. A design with five combat brigades also suffers the fatal flaw of limiting the frontage to 10 rather than 12. Thus, even without using support units, the
3 Arm + 1 Mot
combo is much more powerful.

 

[pnt]

I rarely do anything other than 2x Line Brigade + 2x Support Brigade for my Armored forces

Well, as explained above, 2 and 5 combat brigades per division is the weakest choice due to frontage limitations.

 

[Brownbeard]

My favorite panzer division so far is:

2 x LARM
3 x SP-R-ART

Works like a charm every time. I don't even build any other tanks than LARM in HOI3.

 

[unmerged(158940)]

Well, what ever formations you do have should probably be tailored to your opponent and what ever specific situations you will encounter or plan on manufacturing. Assuming your strategy is the encirclement of army groups, or if you're particularly ambitious 80% or more of a front at once, followed by the reduction of the front by infantry. I'd recommend a penetrating body composed of good old foot infantry supported by artillery with the encircling force composed of what ever is fastest, to the exclusion of the combined arms bonus if you have too*. (I do not actually think you'd have to do this, but i have not checked.) To be complete you'd have to consider the point(s) of penetration, the encircling force, your opponents force, and the presence of any mobile reserves.

Opening of hole should be accomplished with infantry supported by artillery. The IC-Days of a 3 infantry 1 art division is 931 giving you an 8.33 Soft Attack, comparable Soft Attack values using armored units range from 3800 to 5600 IC-Days. Netting you four infantry formations for each armored formation with 4 times the Soft Attack value‡. Or you can get the same or slightly more Soft Attack and more mobile formations. Of course you end up with significantly less Hard Attack, I'll cover why this isn't too relevant towards the end. Defending the point of breakthrough can be more economically achieved by this attacking infantry force as well, they are more defensive, cheaper and thus more numerous, and the disadvantage of their speed is less relevant in this role.

If your encircling force is as fast as is physically possible, you can simply outrun opposition. A 10 KPH force moves two and one half times faster then an infantry force, this can be exaggerated even more by infrastructure destruction during the preparation phase. Multiple points of penetration can also be used if the front is broad enough to ensure encirclement before effective movement by the opposing front can threaten your units and supply lines. Additionally the 2 LA/2 AC formation should use less fuel then any combination of early forces.

Now differentiating your army on these lines introduces weakness. Specifically the presence of any high mobility high Hard Attack reserve can counter and encircle your attacking force. Again I'd recommend using air power† to limit their range of movement, and the shortening of what ever area you intend to encircle. This should concentrate your forces to a greater level then his ensuring you destroy or weaken opposition piecemeal rather then being assaulted with the bulk. Additionally you may try a feint in another area to draw reserves away. This worked particularly well in HOI2 against the AI (I managed to pull 80+ Divisions into a Provence by tossing a series of Army attacks into a single province. Afterward I bombed the infrastructure to 0% immobilizing them.)

But the ultimate counter to your opponents mobile reserve strategy is simply to avoid it. Either by adopting a different strategy, or playing an AI opponent instead of a real person (I presume that the AI isn't sophisticated enough to counter in this way, but I can't say for sure.)

OH and before I forget to preemptively answer this critique ill do it now; If you're considering attacking a province that would require a high amount of Hard Attack to push through, and your goal is to establish a hole in your opponents line to facilitate encirclement, you are attacking the wrong place. AND if every province on his front is stuffed full of mechanized divisions, what are you doing trying to fight this person, you should make friends with him and rule the earth!

‡Optioning for more efficient spending on formations should net you more formations overall. If manpower is the limiting factor and not IC the situation changes, it is possible to spend 7 manpower and 4000 IC-Days (Compared to 11.8 manpower and 900 IC-Days for the infantry formation) on a formation that returns more mobility with a higher SA/HA value. I should probably advocate for this formation, since you can IC whore up to a large number making manpower the more limiting factor, especially for a German player.
*If you can actually design a plan in which your mobile forces never have to fight anything, then you don't need to bother with the combined arms bonus. Although this bonus is significant, something close to a 50% increase in the effectiveness of your formations. (Assuming everyone in the command chain is a Panzer Leader) I'm not flatly advocating that you shouldn't bother with the bonus, just pointing out that it isn't necessary if you never use it. The only scenario I can manufacture at the moment would involve a deep penetration of Soviet Territory. A 500+ KM advance, or basically from the starting line to the Urals. At that point though it also becomes appropriate to mention the fact that you'd be soundly out of range of your HQ units anyway if even in supply.

†Air power could function as more of a linchpin to the overall strategy then the mobile formations themselves.

Additionally a Russian opponent can simply withdraw constantly over the entire front for several months. Only stopping to delay advances, or to defend choke points and river lines. Letting the much maligned partisan
forces mess with you.

Edited for formatting and spelling.

 

[pnt]

My favorite panzer division so far is:
2 x LARM
3 x SP-R-ART
Works like a charm every time. I don't even build any other tanks than LARM in HOI3.

If you want to build a stack of doom (i.e., spamming artillery), 1 L.Arm + 4 SP R Art works even better. Look at dhelmet99's thread about stacks of doom, though.

 

[Toppins]

My favorite armored division is my armored cavalry setup (used in every game I use armor, so sometimes not as Japan), simple and effective, 3 LARM's and 1 AC.

ARM/ARM/MOT/MOT,
ARM/MOT/MOT/SPART,
ARM/MEC/MEC/SPART

...are my favorite medium setups. I don't really like heavy armor...

LARM's usefulness depends a lot on when the war is starting for you, so as Japan in '37 they are wrecking balls (albeit you lack adequate fuel in most cases to field them in force, and unless you plan on starting the 2nd Russo-Japanese war their use thereafter is limited)... for Germany in '39 they are monsters because of the Germany Spearhead affinity, but if you're going to play USA or the Soviets LARM has a more limited role entering the war later. I have 15 divisions (so... 45 brigades...) of LARM as Germany... only slightly less brigade-wise than ARM as of '41.

 

[unmerged(156866)]

Well, what ever formations you do have should probably be tailored to your opponent and what ever specific situations you will encounter or plan on manufacturing. Assuming your strategy is the encirclement of army groups, or if you're particularly ambitious 80% or more of a front at once, followed by the reduction of the front by infantry. I'd recommend a penetrating body composed of good old foot infantry supported by artillery with the encircling force composed of what ever is fastest, to the exclusion of the combined arms bonus if you have too*. (I do not actually think you'd have to do this, but i have not checked.) To be complete you'd have to consider the point(s) of penetration, the encircling force, your opponents force, and the presence of any mobile reserves.

Opening of hole should be accomplished with infantry supported by artillery. The IC-Days of a 3 infantry 1 art division is 931 giving you an 8.33 Soft Attack, comparable Soft Attack values using armored units range from 3800 to 5600 IC-Days. Netting you four infantry formations for each armored formation with 4 times the Soft Attack value‡. Or you can get the same or slightly more Soft Attack and more mobile formations. Of course you end up with significantly less Hard Attack, I'll cover why this isn't too relevant towards the end. Defending the point of breakthrough can be more economically achieved by this attacking infantry force as well, they are more defensive, cheaper and thus more numerous, and the disadvantage of their speed is less relevant in this role.

If your encircling force is as fast as is physically possible, you can simply outrun opposition. A 10 KPH force moves two and one half times faster then an infantry force, this can be exaggerated even more by infrastructure destruction during the preparation phase. Multiple points of penetration can also be used if the front is broad enough to ensure encirclement before effective movement by the opposing front can threaten your units and supply lines. Additionally the 2 LA/2 AC formation should use less fuel then any combination of early forces.

Now differentiating your army on these lines introduces weakness. Specifically the presence of any high mobility high Hard Attack reserve can counter and encircle your attacking force. Again I'd recommend using air power† to limit their range of movement, and the shortening of what ever area you intend to encircle. This should concentrate your forces to a greater level then his ensuring you destroy or weaken opposition piecemeal rather then being assaulted with the bulk. Additionally you may try a feint in another area to draw reserves away. This worked particularly well in HOI2 against the AI (I managed to pull 80+ Divisions into a Provence by tossing a series of Army attacks into a single province. Afterward I bombed the infrastructure to 0% immobilizing them.)

But the ultimate counter to your opponents mobile reserve strategy is simply to avoid it. Either by adopting a different strategy, or playing an AI opponent instead of a real person (I presume that the AI isn't sophisticated enough to counter in this way, but I can't say for sure.)

OH and before I forget to preemptively answer this critique ill do it now; If you're considering attacking a province that would require a high amount of Hard Attack to push through, and your goal is to establish a hole in your opponents line to facilitate encirclement, you are attacking the wrong place. AND if every province on his front is stuffed full of mechanized divisions, what are you doing trying to fight this person, you should make friends with him and rule the earth!

‡Optioning for more efficient spending on formations should net you more formations overall. If manpower is the limiting factor and not IC the situation changes, it is possible to spend 7 manpower and 4000 IC-Days (Compared to 11.8 manpower and 900 IC-Days for the infantry formation) on a formation that returns more mobility with a higher SA/HA value. I should probably advocate for this formation, since you can IC whore up to a large number making manpower the more limiting factor, especially for a German player.
*If you can actually design a plan in which your mobile forces never have to fight anything, then you don't need to bother with the combined arms bonus. Although this bonus is significant, something close to a 50% increase in the effectiveness of your formations. (Assuming everyone in the command chain is a Panzer Leader) I'm not flatly advocating that you shouldn't bother with the bonus, just pointing out that it isn't necessary if you never use it. The only scenario I can manufacture at the moment would involve a deep penetration of Soviet Territory. A 500+ KM advance, or basically from the starting line to the Urals. At that point though it also becomes appropriate to mention the fact that you'd be soundly out of range of your HQ units anyway if even in supply.

†Air power could function as more of a linchpin to the overall strategy then the mobile formations themselves.

Additionally a Russian opponent can simply withdraw constantly over the entire front for several months. Only stopping to delay advances, or to defend choke points and river lines. Letting the much maligned partisan
forces mess with you.

Edited for formatting and spelling.

Awesome post!

 

[P3D]

You need basically four types of stacks/divisions:
a/ Hold the line - i.e. INF/MIL with whatever brigades
b/ Breakthrough - to concentrate as much force as possible.
c/ Exploitation - to have large number of fast divisions available
d/ specialist.

So consider b/ and c/. With the four main constraints:
- IC
- Manpower
- Fuel

Leadership can be ignored here, as optimizing for the other variables won't be far from optimal in the # of divisions either.

If you look at it, with the introduced support brigades, MOT and MEC are very expensive in different way. MOT is just too expensive in IC and MP/leadership for the limited offensive capacities. If one has a lot of MP and decent IC, LA+MOT is the ideal for exploitation (SOV, JAP) despite slightly slower speed. Disadvantage is the abysmal Hard Attack.
LA: ARM is just superior after 1940, build them only for the LA+MOT exploitation corps. Unless your enemy has mobile forces available (multiplayer issue).
MEC: They have similar attack (average of SA and SA) to ARM, and cost the same. Faster than MOT for exploitation if you have the IC. But MP-wise you are better building ARM (3.00 vs. 2.33) and support units. Their only advantage vs. ARM is the lower fuel consumption. If your main concern is fuel not leaderships
ARM: the best overall unit, period. Somewhat high fuel consumption though.
HA: They are slow which is the main reason why not to use them. Not much better stats than ARM anyways and they won't take more hits to kill at all. And heavy tank armor will slow down your TDs. I won't build them even if they'd cost as much as ARM. As they cost more, forget it.
AC: They are cheap in IC and MP, but with low attack. Their big disadvantage is the 100 leadership cost. If they'd cost 50 I might build them.
SpArt, TD: mix them with your ARM depending on your opposition, about the same speed (if you did not research HA armor). They are pretty effective fuel-wise, and SpArt is also a soft unit. TD+SpArt mixes are has about the same punch as similar amount of MEC and are more affordable.

Bottom line: mix TD+SpArt with ARM for breakthrough, LARM+mot for exploitation. If you really want speed, don't mix LA with anything else (perhaps AC, but that is a drain on leadership in any quantities), they are there to overrun enemy divisions and take territory - and losses until slower units catch up.

 

[Szun]

after experimenting a while i desided to use :

1 arm 2 mot 1 TD 1 sp_art (5 brigs)
1 arm 2 mech 1 TD 1 sp_art

it has the best cost to power/hardness ratio and its on the low side of the Comb. A. bonus softness

also after the -1 frontage tech its 3 frontage and you can attack with 4 divison (12 frontage)

or combine them with 2 frontage Mech

2 mech 1 TD 2 Sp_art


p.s. a little tip if you want speed over firepower... research tank engine and reliability and forgo armor and gun, it speeds tanks up like crasy
drawback, defense and soft/hardattack goning to be on the low side


i allways try to get mech brigs as fast as i can...

 

[Laurwin]

Well, as explained above, 2 and 5 combat brigades per division is the weakest choice due to frontage limitations.

spearhead tech gives a reduced frontage for armour I think. but 4 arm+ 1 mot is a quite expensive divisions in any case. I would go for some sort of combination of mech + arm + sp-arty/sp-at

has anyone had success with weak armoured divisions/single brigades? I mean it should offer somewhat better chances of actually exploiting a breakthrough in the strategic sense. More weaker armoured divisions would divide the combat delay penalty over a larger number of divisions for instance.

 

[pnt]

Bottom line: mix TD+SpArt with ARM for breakthrough, LARM+mot for exploitation. If you really want speed, don't mix LA with anything else (perhaps AC, but that is a drain on leadership in any quantities), they are there to overrun enemy divisions and take territory - and losses until slower units catch up.

Your analysis does follow the same lines i sketched in another thread some time ago.
http://forum.paradoxplaza.com/forum/showthread.php?p=10022929
I do, however, not share all of your conclusions.

The main problem is that you are neglecting the fact that officers and techs both drain the same leadership pool. Thus, by selecting what you focus on, you can gain either a technological advantage, or support more units.

My main concern is with TD. It is extremely tech (leadership) hungry. You need not only L.Arm and Arm techs for it, but also some H.Arm and AT. And it is rather useless in the breakthrough role, since its hard attack does not affect the Inf divisions.

If you compare (using 1947 stats)
3 Arm + 2 SP Art (SA:41.13, HA: 29.45, soft: 40%, speed: 9)
with
3 Arm + 1 SP Art + 1 TD (SA: 35.06, HA: 37.22, soft: 31%, speed 7.5)
you immediately see that you lose you combined arms bonus since your softness is below 33%. The division without TD is also 20% faster, and has better soft attack, which is crucial for breaking through.

If you want to restore the combined arms bonus, you must lose one of the combat brigades, i.e., replace an Arm with a TD. You division the looks like
2 Arm + 2 SP Art + 1 TD (SA: 34.8, HA: 31.12, soft: 41%, speed 7.5)
It is inferior to the original one in all respects except HA, and also suffers from the fact that it only can present a frontage of 10 rather than 12.

I would rather have the baseline
3 Arm + 1 Mot (SA: 31.19, HA: 27.41, soft: 36%, speed 8.7)
than mixing in any TDs in the breakthrough divisions.

Of course, for exploitation TDs are even worse. However, your L.Arm + Mot may not be ideal for exploitation either. Mot limits the speed to a mere 8.7, which is lower than a 3 Arm + AC or 3 Arm + 2 SP Art division! Combining L.Arm with Mot only makes sense very early in the war - and what do you do then? Disband them? Mixing L. Arm with AC produces the same problem. AC maxes out at 9.9, making it much more suitable to mix with Arm than L. Arm (max speed 11). The latter is, on the other hand ideal to mix with SP R Art (also speed 11), which can bring up the softness above combined arms threshold.

The main function of AC is that it allows you to make a
3 Arm + 1 AC (SA: 30.99, HA: 25.32, soft: 34%, speed: 9)
division, which is faster and as powerful as the 3 Arm + 1 Mot, despite its lower frontage, but has lower supply consumption and frontage.

 

[pnt]

spearhead tech gives a reduced frontage for armour

Good point! I have indeed assumed that one has spearhead. Otherwise frontage indeed becomes an issue. But it is easy to get by mid 1939.

 

[pnt]

To summarize, there seem to be three design approaches that stand out:


1. Baseline (all divisions with 4 combat brigades)
3 Arm + 1 Mot (breakthrough)
1941: SA: 20.39, HA: 17.66, soft: 36.5%, speed: 7.5
1947: SA: 31.19, HA: 27.41, soft: 36.0%, speed: 8.7
all: supply: 4.99, fuel: 5.17, IC days: 5690, MP: 10.34

2 L.Arm + 2 Mec (exploitation)
1941: SA: 20.54, HA: 10.94, soft: 50.5%, speed: 9.8
1947: SA: 28.94, HA: 16.64, soft: 49.0%, speed: 10.4
all: supply: 4.66, fuel: 4.0, IC days: 4426, MP: 10.66


2. Blitzkrieg (all divisions with 3 combat brigades)
3 Arm + 1 AC (breakthrough)
1941: SA: 20.39, HA: 16.32, soft: 34.2%, speed: 7.5
1947: SA: 30.99, HA: 25.32, soft: 33.7%, speed: 9.0
all: supply: 4.32, fuel: 4.83, IC days: 5496, MP: 8.66

3 L.Arm + 1 SP R Art (exploitation)
1941: SA: 16.01, HA: 9.01, soft: 40.0%, speed: 9.5
1947: SA: 23.51, HA: 13.51, soft: 40.0%, speed: 11.0
all: supply: 4.0, fuel: 3.4, IC days: 3638, MP: 8.32


3. Superior Firepower (all divisions with 3 combat brigades)
3 Arm + 2 SP Art (breakthrough)
1941: SA: 28.53, HA: 19.85, soft: 40.0%, speed: 7.5
1947: SA: 41.13, HA: 29.45, soft: 40.0%, speed: 9.0
all: supply: 5.33, fuel: 5.5, IC days: 6621, MP: 9.65

2 L.Arm + 1 Mec (exploitation)
1941: SA: 13.94, HA: 8.14, soft: 43.7%, speed: 9.8
1947: SA: 19.64, HA: 12.49, soft: 42.7%, speed: 10.4
all: supply: 3.33, fuel: 3.0, IC days: 3226, MP: 7.66

Please note that all provide combined arms bonus (softness 33%-67%). The optimization involves also the tech (leadership) requirements. The Baseline assumes no research of any support units, and offers the flexibility of splitting the exploitation division into two. The Blitzkrieg one requires only AC and rocket Art (also for the infantry). The Firepower option requires artillery research, but nothing more. All three variants can put 12 combat brigades at the front (spearhead doctrine assumed).

If you post other suggestion, please calculate the corresponding values for reference!

 

[P3D]

I won't research HA for the TD for a single tech which slows the TD down, so why bother. One would research LA anyways, so it's only a single tech to keep up, and more rewarding vs. SpArt.
IMHO MOT is not a good idea at all, compared to SPArt to provide softness.
TD is also close to perfect in 2MEC+1TD divisions.

Note, I will mostly play MP after the game is straightened out, and there one will have to take hard attack into account. Even for breakthrough, going for soft attack won't be a solution when I'd meet counterattacks from other combined arms units.

I agree that the priority is to keep the CA bonus in mind.

Your analysis does follow the same lines i sketched in another thread some time ago.
http://forum.paradoxplaza.com/forum/showthread.php?p=10022929
I do, however, not share all of your conclusions.

The main problem is that you are neglecting the fact that officers and techs both drain the same leadership pool. Thus, by selecting what you focus on, you can gain either a technological advantage, or support more units.

My main concern is with TD. It is extremely tech (leadership) hungry. You need not only L.Arm and Arm techs for it, but also some H.Arm and AT. And it is rather useless in the breakthrough role, since its hard attack does not affect the Inf divisions.

If you compare (using 1947 stats)
3 Arm + 2 SP Art (SA:41.13, HA: 29.45, soft: 40%, speed: 9)
with
3 Arm + 1 SP Art + 1 TD (SA: 35.06, HA: 37.22, soft: 31%, speed 7.5)
you immediately see that you lose you combined arms bonus since your softness is below 33%. The division without TD is also 20% faster, and has better soft attack, which is crucial for breaking through.

If you want to restore the combined arms bonus, you must lose one of the combat brigades, i.e., replace an Arm with a TD. You division the looks like
2 Arm + 2 SP Art + 1 TD (SA: 34.8, HA: 31.12, soft: 41%, speed 7.5)
It is inferior to the original one in all respects except HA, and also suffers from the fact that it only can present a frontage of 10 rather than 12.

I would rather have the baseline
3 Arm + 1 Mot (SA: 31.19, HA: 27.41, soft: 36%, speed 8.7)
than mixing in any TDs in the breakthrough divisions.

Of course, for exploitation TDs are even worse. However, your L.Arm + Mot may not be ideal for exploitation either. Mot limits the speed to a mere 8.7, which is lower than a 3 Arm + AC or 3 Arm + 2 SP Art division! Combining L.Arm with Mot only makes sense very early in the war - and what do you do then? Disband them? Mixing L. Arm with AC produces the same problem. AC maxes out at 9.9, making it much more suitable to mix with Arm than L. Arm (max speed 11). The latter is, on the other hand ideal to mix with SP R Art (also speed 11), which can bring up the softness above combined arms threshold.

The main function of AC is that it allows you to make a
3 Arm + 1 AC (SA: 30.99, HA: 25.32, soft: 34%, speed: 9)
division, which is faster and as powerful as the 3 Arm + 1 Mot, despite its lower frontage, but has lower supply consumption and frontage.