Great victory, what can I say.

Historically soviets suffered huge casualties in 1941, actualy major forces were wiped out several times. But they replaced them even faster. And it (ability to rebuild entire army from scratch in 2-3 turns) is not something, what you want to be modelled in game, since this way soviets will be much stronger, then they are now.
I have to say, that thing which hurt most (i believe axis and allies, maybe allies a bit more) is extensive research randomness.
You can go for dog fight labs with USSR from very beginning of the game, and still have 8 air combat only in mid 1944. Or in 1942. This randomness is not good thing, if you ask me.