This goes back to my old request I posted 10 times in the wishlist. Take the F4u-1d and the F4u-1c for example - same aircraft, different guns.
Have the same plane, with perk weapons. I think it would probably not work since it would have to re-do the game, but just copy the il-2 over and give it a perk option for 37mm's maybe 6 perks for it. I mean seriously all one has to do is spray and you win.
or add the Ju-87G with 37mm guns that are not perked, but I believe it had 6 rounds per gun (not sure on this believe its correct)
Il-2 perked for the cannon load and a flying tank, Ju-87 thats slow, heavy armed, but not armored.
/Makes sense to me I think? lol