Some other things i think are unbalanced:
Naval-bombers , they are just not realy effective vs battleships.
Lets see at lvl3 dd 30hp 4 aa , cl 50 hp 8.5 aa , bb 75hp 6 aa vs lvl3 navbomber 25 hp 7,5 ship attack.
DD needs 6,25 shots to kill 1 plane , cl ~3 ,bb ~4,2 . Plane needs 4 bomb to kill dd , 6,66 to kill a cl , 10 to kill a bb. From the look of it ,bb have too much aa def ,as cl-s meant to be the aa defender of the fleet as there are no carriers in the game, this is fine.
But from my experience even a smaller fleet without cl-s attacked by a larger naval bomber squadron ,does pretty good dmg on those bombers. I think bb-s without fighter cover and cl support should die horribly vs naval bombers . At least naval bombers are good vs subs.
Strategy bombers : their range is so small IRL they could easily fly 2000km , so thats 1000km range more or less for earlier models ,but in this game most things have larger ranges like fighters/missiles ,and arties. They should be able to fly as far as they could in RL. 375km for lvl1 ?:O comeon it should 600km or more , the point of these planes to bomb way behind the front the enemy buildings , but they cant reach their targets , with their current range , they can fly a slightly farther than tactical bombers ,but they are not effective vs units ... they need a range boost.
Rockets : from the look of it these are insanely good , they realy shouldnt dmg troops much. They are ALWAYS cost effective and have way too long range , they act as a modern day scud comeon... oh and there is no real defense vs them.
Infantry: I dont get why they have only 15 hp , while tanks have 20 25 45... they are already slow and cost 1500mp.
Arty+aa+anti-tank:why they need 1000 mp too much.
Oh and what I experiecned so far : everybody mass build tanks especially lights