I think, for that price, there is no requaired buff in stats but I think, it would be enough to reduce veterancy requirements by 20% or 15% and make it a bit cheaper in MP (to 280/270 or even 250). What do you think about it?
Something needs to be done. Maybe just swap it out for the 34/85 since according to Soviet records, they built thousands more of the 34/85 than they did 34/76. Then you can go to the 2 34/85 commanders and change the 34/85 unlock into a 6 or 7 CP T34/76. This way SU gets a stock main line battle tank and can have the option of getting an early 34/76 but only doctrinally. You would have to tweak the cost a little bit since it would come so early but it is so underwhelming in it's current state that it might be fine as is. It needs to have a period of time to get vetted up anyway before the rest of the big boys come in or it will be even more hopeless.