I have a few ideas (looong speech)
Change the tech tree
Instead of technologies being set defined points which a country either has or hasn't, make them into diffused points on a spectrum. To illustrate this, V2 has 150 technologies, spread in 5 categories of which there are 5 sub categories. When you're researching railroads you're not researching anything else. To illustrate my point, assume this were the tech tree in V2.
Each tech branch is, by default, researched at ''speed 1''. The player has, however, access to, say, 5 ''blocks''. Each block represents the effort and resources the player is investing in that particular tech tree, and increases the tech research to that tech branch (1 block is 1+1 speed, 2 is 2+1 etc). Hence to research Railroads faster, simply use the blocks to indicate that the state is more concerned with railroads than, say navy organisation.
As for technologies no loger existing as set defined points, they can be broken down into inventions. Take Light Armament as an example. You can research Muzzle Loaded Rifles (combat width -2) , Breech loaded rifles (cw -3) etc etc. Instead inventions with (perhaps) some historical rifles could take the stead and reduce the combat width by -1 each. Thus both techs could be substituted with a few invetions that have the probability to be discovered once a certain amount of military research points in that branch have been reached.
At the same time, countries who are way ahead in a tech group than their neighbours get a negative research point modifier gain. Similarily, those who lag behind get a positive RP modifier.
Also military tech should be researched much faster if there are units in active combat ( an active war )
MILITARY REFORMS
Assuming the interface is the same, just like the politics tab has social and political reforms, I think the military tab should have military reforms that concern training, equipment, recruitment programs, mobilization etc. (some of which I will discuss)
Mobilization
Use conscription instead. I think HPM did this. No conscription countries can still recruit a voluntary army (depending on the % of jingoism or pro-military support in the country, this will vary) Countries with 1 year conscription get , say factory throughput -1% and the mobilised army gets an organisation (or morale, strenght, whatever, im not that knowledgeable) modifier of a particular value, 2 year conscription gets a slightly better combat modifier and a bigger factory throughput penalty, (Doubt any country ever planned a 4 year conscription program so I'll end at 3)
Also, regarding all mobilised units being all infantry, why not allow to stockpile artillery and have a portion of your conscripts be trained in artillery use?
Thirdly, more detail regarding these conscript units. Each country at the time of mobilization knew when and how many soliders it was mobilizing. This should be also done in V3.
Mobilization was not a chaotic process but was actually pretty well structured, with each province having its own little military departament and a center with training grounds for the conscripts. I think V3 if it comes out, should definitely try to mimmick that to as high a degree as possible ( I <3 V2 and ck2 because of of the complexity and detail (within reason though), not the simplicity and dumbing down).
There could also be the ability to decide just how many troops you want to mobilise. Great War mobilization obviously being the ''get everyone you can into a uniform and give them a gun'' , whereas low-threat mobilization would be just mobilizing enough men to supplement the main standing army.
(Maybe a little slider on how many conscripts you wanna mobilize would solve the issue?)
And obviously reserves.. Each year all those previously 18 year old turn 19 (assuming 19 is the military age) and are fit to be consripted. I'll leave you with this suggestion, I dont have a good solution myself.
Equipment
We all know that not every army equipped all its men with the newest guns and artillery. The military maintenance slider in economy should be dismantled into its components. Spend much on artillery? Artillery units get the newest big guns that the tech allows, the longer the slider is in the high range the more units in that brigade get the newer guns. Same with rifles. All units got the newest guns and fund them 0? Well rifles and guns break....
As for combat, it could initially function the way it did in V2 up to say 1895 and after that switch to the front warfare of Hoi4. It would help to manage hundreds of units in the late game and maybe (hopefully) prevent the game from slowing down on every great war.
Diplomacy
Mainly focusing on Crises here, just like rebels they become an issue late game with a major diplomatic crisis occurring every 6 months. This leads to quite amusing results like, in my swiss campaign, I've finished the 6th world war by 1934. Crises did sometimes lead to war but most of the time they were peacefully resolved. Late game however, the AI has had enough time to conquer from eachother and control cored areas, leading to annual crises which, not rarely, end up with the backing superpower imposing demands which the opposition just wont accept, leading to a world war. I like the alternative history side of the game, dont get me wrong, but 6 world wars by 1934 is just a bit too absurd. The game should have a mechanism that does lead to tensions high enough to cause a Great war, but once that one Great war happens, the sides should adopt a more compromisable approach to foreign politics (like British and french appeasment of Nazi Germany) I think the problem here lies with the fact that the AI does not try to avoid a world war, something everyone tried to avoid even before WW1 (which proved unsuccessful following the 1914 crisis). No offence to anyone, but Romania should stfu about siebeburgen after a crisis revolving it has been (keyword) resolved. Same goes to Italy and Western Afghanistan. Once a crisis is resolved, it should stay resolved as long as the balance of power remains stable.
There should be an option to draft and send an Ultimatum. Its a cute way to get what you want without going to a major conflict. Ultimatum possibilites can include military access, demand province (just one max!), transfer sphere, unification, and more.
As for demanding province, each country can have the right to send an ultimatum regarding the transfer of one region it has a core on twice in the game, one between 1836 and 1886 and the other 1886-1936.
World tension and national security
One of the things i picked up from watching hoi4 lets plays, world tension and I just have this idea on how to ensure a Great war erupts without romania provoking 15 diplomatic crises.
I find it funny how the very issues that provoked WW1 are absent from V2. Lack of diplomatic and political intrigue, lack of the complex system of alliances that balanced the power in europe and ultimately led to the war, no issues anyone has with a country becoming simply OP and steamrolling smaller nations around it. This led me to develop this idea. There should be a tab in diplomacy with alliances, and alliance strenght (the military score of its members combined) as well as alliance integrity (Italy very low alliance integrity with Austria, as an example) Each alliance kind of acts like a state. It opposes an alliance with which it has a disputed claims, matching military and industrial score. Whereas the Entene mightn't mobilise against the british conquest of Burma, it would if the integrity is high against the Triple Alliance.
Tension can be measured (but does not have to, I dont really have a good system) by comparing the combined military and half the industrial score of nations. Lets say that at the start date, there exists a particular balance of power in europe ( like it did). Say, for every 100 British Power points, France has 90, Russia has 85, Prussia has 80 and Austria has 70 (and some other nations have their own). Now the formation of NGF causes Prussia to absorb all those smaller states (each with their own power points) to create a NGF with 100 power points. This increases tensions with France significantly, as NGF wants to for Germany but to do so, it needs to get its cores in alsace-lorraine. Tension also increases because now France is overtaken and the balance of power shifted, destabilising the existing peace. And finally, after germany is formed, it gets 130 PP, upsetting this balance even further. France gets low national security, Other powers like Russia and UK start to be a bit worried about the rise of Germany, making them more likely to join a rivalling alliance against germany.
Same goes with 1914. Russia industrialises and its PP rises. France switched to a 3 year consription program, so now they'll have a bigger army, and both countries are allied. So if Russia now has, say 110 PP and france has 100, their alliance has a total of 210 PP, whereas Germany-Austria has 200. This increases tensions sharply. Tensions also increase when one country gains (or loses) these power points rather quickly. Just like capitalists analyse the trade window for high profit goods to produce, the military command analyses the shifting power balance in its proximity and reacts accordingly. A country rapidly gaining PPs would come at odds with its neighbours, but in favours with neighbours neighbours, and the reverse for a quick loss.
That being said, its likely that the existing formulae for calculating military and industrial points would need revision if such a system were really implemented
National Security is basically a measure of how stable the current balance of power is, projected on each country. If germany has a low military score and is at odds with an alliance of France and Russia, national security goes down. This provokes more support for pro-military and jingoism issues, adds a morale and organisation bonus (a little one) to all units, as well as increaed tax efficiency and administration ( everyone in the country demands more effective governship when the existence of their state is at risk). This ties with the high level of nationalism in europe which rocketed even higher during crises and national threats. Low National security allows political and military reforms to be passed with less upper-house support (If such reforms grant an advantage). The downside is, countries with low national security seek higher alliance integrity (if they belong to one), and are much more likely to demand concessions in crises if they have sufficient GP backing. Ultimately NS tries to close in the gap between the nation and its rivals.
National unity is also a nice concept, though it may need some adjusting.
Budget, Production and Trade
More sliders in the budget window, like a slider for social projects (schools, hospitals)
A slightly more sensible factory construction and operation. Investors seem to build factories that produce goods with the highest price (idk how it actually works) and all in the wrong places. I've got a province with coal and iron, they build a steel factory in an all grain and fuit province. It just doesnt make sense to me. Correct me if Im wrong though. Once I stopped subsidising my factories in 1905 about a quarter of them went bankrupt because... reasons. Country-specific tarrifs would be nice. You dont wanna sell artillery to your enemy for the same price as you sell it to your ally. Also there should be a way to stop the construction of certain factories or railroads.
A description of what modifiers forts give would be nice ( had to read the wiki to know)
Reduce the time it take to build military factories at war
Politics
Player may not always be given full control of the upper house. In democracy and HM's goverment, the upper house may vote to go to war. In both cases, the player can choose to undertake a chain of events to prevent or encourage a war to break out (similar chain to elections) At the end of the voting, you can either agree or disagree with the outcome. If you agree with the upper house voting, you may be drawn into a war (or declined one ) you may not exactly have wanted. If you decline, it increases conciousness and militancy of pops who oppose your decision ( but reduces militancy and conciousness of the pops that share your view) Declining the upper house decision changes goverment type. Democracy becomes Presidential Dictatorship and HM's becomes Prussian constitutionalism.
In all other forms of goverment, votings either dont take place at all or must be authorised by the leader ( In germany, the kaiser could nullify and retry legislations as much as he wanted until he got the result he wanted)
Autonomy would be a nice concept.
more political and social reforms also a good bonus.
Why prevent railroads from being constructed?
Well controlling railroads should give the army a moverment speed modifier. It should also give them better supplies. Perhaps you're russia and you dont want a well supplied german army in your ukraine. Destroy the railroads in your western provinces (destroying objects should be avaliable) As for supplies, its rather straigh forward, the further away the army is from the closest owned and cored province, the less efficiently supplies and reinforcements reach the troops ( food slider maxed, distance prevents all the food from reaching the troops ). I found it weird the way there was naval range but no similar land range. Railroads obviously increase the land range, and you can construct them in occupied regions ( but rebel partisans can sabotage them)
Rarer but more intelligent rebels.
I've created a true paradise. Low taxes for everyone, 2% tarrifs, high social spending, most social and political reforms passed, and yet communists spawn the shit out of me and desire to
destroy the free economy and politics I've created. There is little sense why people would revolt and end the dream I gave them.
Rebels should also not just stand there and wait to be crushed. Rebellions should be rarer but better timed and better planned. Even though V2 tries to mimmick the rising communist and fascist agendas in europe, spawning rebels is not a way to do this. Even through the chaos that ensued after ww1 only one country had its goverment replaced by communists ( Russia ) and fascists ( Italy ). Nazis won the 1933 democratic election.
Stop entire brigades from deflecting to rebels. Not only is it silly that an entire brigade deflects but it also leads to the tedious fixing. Finding which units deflected, recruiting these units, sending and joining the armies.
Alternatively allow to create a ''template army'' of the player's design, then once there is enough solider pops to recruit those you recruit an army as a whole rather than unit by unit
National ideas would be nice
Introduce characters. It doesnt have to follow CK2, hoi4 style seems good, but its a bit obvious that the country's policy and attitude depended on the leader. Leaders should provide a
few modifiers for their country
With this, sponsor political assasination should be an option, and a crisis regarding such an assasination should be possible (franz ferdinand?)
On sponsoring death, sponsor rebels should be an option, but its discovery should, by definition lead to an Ultimatum (obviously)
Infamy should reflect the willingness of contries to ally with eachother. If one country has high infamy, it should definitely influence alliance integrity.
More starting dates
My personal list of candidates runs like this, 1815 (Congress Vienna), 1836 (standard) , 1843 (Opium wars) , 1854 (Crimean war) , 1861 (Us Civil war) , 1866 (Unification of germany), 1875 (Russo turkish war and scramble for africa), 1893 ( Pax Britannia and oncoming Us-spanish war) 1902 ( Russian troubles ) 1909 (Road to war) 1914 ( The great war) 1915 (Gorlice-Tarnov and Italy at war), 1916 (Verdun, Somme and Brusilov) 1917 ( Brest-Litovsk and Russian civil war), 1918 (The spring offensive and last allied offensives) 1919 (Versailles and Polish-Soviet war)