It feels like many of my teamgames ostheer goes t4 for panthers and support them with PG spam. I do it as well. And if you go in to late game as soviet, how do you counter the mass panther/pgs? If you dont get the first panther when it shows it face, they start to get pesky to deal with.
Counter Panther/Pgren spam? HA, there is no counter. There is a reason everyone and their mother uses it and it's because it's uncounterable. Go t34/76 or 85 and they will be annihilated by the panthers. Su-85s might be able to manage the panthers, but then there are the pgren blobs. Even if you do hold off the pgren blobs, you are forced onto the defensive and then its just a matter of time before they spam opels and you get hit with constant call-ins.
The truth is in larger team games, the only way for the soviets to win is to never let the germans get anywhere near the same amount of resources your team is and to constantly harrass for their opels and caches. If the game is anywhere near close going into the late game it's game over.