1. Add the Maxim MG Team. This is needed, and definitely should be made to not go into buildings, so yes, function about the same as an AT gun.
2. Add an armored car like the Ba-64. I was surprised to see that no Soviet armored cars were in the original make. Since the other 4 factions of the original CoH all have them, I think the Soviets should as well.
SU-85 shouldn't be upgradable to the SU-100. I have found that the SU-100 wasn't even that common, and it tips the balances a little too much. Just stick with the plain SU-85.
By July 1945, 2,335 SU-100s had been built.
QuoteBy July 1945, 2,335 SU-100s had been built.-Wikipediathats a lot more than the amount of King Tigers built, which was less then 500. In CoH it doesn't really matter how rare a specific unit was in reality, if it existed, it's an option.
I do rather like the idea though of a wheelable MG team, using something like the PM1910 Maxim. I bet devs could just reuse the model assets from the US .30 cal or British Vickers, since they look a lot like the M1910, and just reskin it and reuse the AT gun team code.