I tried the latest version and I must say wow. With what you got now the next version will kick even more ass.
But heres what I think you should do.
1: The War factory for the USA should have the tanks droped off like at the com center because I don't think most tanks are built on the battle front. If speed is a problem then make a plane drop a create full of parts when you click to build a tank.
2: You have alot of gen defult things like the sluppy pad and some barrles and creates and stuff. I bet that is already in the works to be changed.
3: A new dozer is needed.
4: Maybe in the next version have one small single player level.
5: I would remove the gens for all teams just for to lighten the load (doesn't sound right)
Thats my ideas/and thingys.
If you need a mappy give me a shout.