T-34/85s never used top MG gunners and we will see what can we do with IS-2 later, when the new model is being done.
About the ATG, nope. It is fine as it and we don't need two different at guns to perform that job. We already have the AT rifles and the ZiS-2, Soviets doesn't need anything else.
The ability you suggest for the Tank Hunters sounds like the PE ATHT "Tread break" ability... and we don't like rip-offs, not that they need it if they are able to lay down AT mines that do a similar effect
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