I have been trying to use paratroopers as Turkey vs Greece, with them i can eliminate their entire army within a week, but so can i without paratroopers, it just seems like a WIN MORE thing, not something that makes or breaks a campaign.From what I remember before Scout Planes & Espionage (It should be easier/less risky now).: drop them on probably empty tiles that are connected, and will be reached by your regular troops shortly too it will help with encirclements and thus help you win faster. You want tiles for your paratroopers to retreat too if they land on or next to an enemy unit so having other tiles taken by unopposed paratroopers is supposed to do that ergo don't just drop 5 of those division on the same spot. You also want to use general abilities that help your paratroopers - like glider planes and all other support you can get - CAS, Naval Bombardment and Intel.
A more risky approach is during Naval Landings, especially on single tile Islands to support your Marines, if the landing is going well order the Paratroopers to assault too to quickly break the defenders - downside if the fight takes too long or turns against you the low org paratroopers will be wiped out.
They can also serve to delay reinforcements if for examplet the direct way between the Siegfried line and the rest of Germany is being occupied by them while the Allies attack from the Maginot line - even worse if they manage to get Airports as that makes it harder for Germany to defend its Skies. Seen in the Youtuber VS Devs video where it happend (and failed) with 1 battalion paratroopers though.
But in the end win faster/mess with the AI is pretty much the motto of these troops cause anything you manage to do with them you probably could without and considering the extra XP and research cost to get them they are more of a roleplay thing than anything else in this game.
I at least make them 10 width, but any more that is a waste I thinkParatroopers seem best used in single-battalion-divisions - they'll lose if they get into any real combat anyway, so why risk an entire division?
The way i attack ports is like 3+3 divisions attacking port, 3 divisions first wave, then 3 divisions on second wave when the first 3 are tired. I also launch 4 divisions on the sides of the port to attack the port garrison by surrounding or just plainly attacking.The best way to use marines is in templates with tanks that you use for direct naval-->land assaults. Terrain bonuses/penalties are averaged across a division, so marine infantry battalions can effectively make tanks float. This pretty much completely invalidates the existence of dedicated amphibious tanks, which require significantly more research and industrial setup than marine infantry.
Other divisions outperform marines in pretty much every other use-case, however. Marines are infantry, so don't expect them to dislodge much without armor or air support. If all you need is some units to engage in combat for your CAS to do the work, then normal infantry is sufficient. Marines don't even take much fewer casualties in amphibious combat compared to normal infantry, since they have significantly reduced HP for some reason. Also, it should be noted that amphibious combat in general should be pretty rare in SP games, as the best method for securing ports is simply to drive some tanks on undefended tiles adjacent to ports, and then attack the ports by land. Experienced players in MP will set up their defenses to counter this, but the AI isn't smart enough to do so.
In my view, there are no "legitimate" uses of paratroopers in the game. They're only ever used to exploit the AI, e.g. capturing undefended ports to cheese through naval supremacy, taking VPs to force early capitulation (doing this on France is notorious), etc. They make the AI absolutely freak out with frontline management, so simply spraying a bunch of paratroopers in the enemy's backline will make the AI abandon large chunks of the frontline in some areas, and throw a bunch of divisions into obvious encirclements in others. Paratroopers ostensibly require air superiority to use, but it's not difficult to cheese through this requirement once you understand how the AI allocates planes to air regions.