Yak-3
P-63
Mig-3
Tu-2 or Pe-2
IL-4
Ki-43
Ki-44
Ki-45
J2M
D4Y
G4M
I think the only two planes that would see any use in the MA are the Yak-3 and the P-63. The P-63 never saw any use with the USAAF, but the VVA used it.
Since the focus of the game has been consistantly moving away from air combat for years, I think it would be nice to have the GV system fleshed out a bit with more tanks, self-propelled artillery, and tank destroyers / assault guns.
I think that assault guns / TDs would add a fun element to the tank game - something like the Jagdpanzer IV, Hetzer, SU-85 (the SU-76 would be fun too, but the gun would be less than useful I suspect). I think the SU-85 would be the best choice, as it would give the Soviet tank set an AFV that actually has some value in armored combat, but the Hetzer would be pretty cool too.
I think it might also also be fun to be able to spawn a battery of fixed artillery / AT guns / AA Mgs .. almost like a mini-base. Perhaps the base could have GV supplies also