I dont know how good the german opponents I have been meeting in 2v2 auto have been, but they definitely weren't leaderboard tops. What I've been doing however as soviets in 2v2 is to do the same thing two PE players (similar tech structure) would do in old coh. In ancient coh
f two PE playes would often do a combined t1t3 + t2+t4 meaning they had all unit types available. I think soviets need to do this too.
This has worked well vs both heavy grens, heavy mg and combinations:
Soviet1: goes 3-4 conscripts and then builds a sniper and then techs to t3 getting a t70 or t34 out.
Soviet2: goes a few conscrips and then techs to early m3 flamers and then techs to su85s.
If they are contending with you by doing well with their infantry the stealing of a mg42 has consolidated many games. If you are even on fuel you get out your armor before they do a soviets and this is a window of opportunity to take vps and start defending.
I also find that soviets should focus on letting their tanks kill the german infantry and not fight the p4s and ostwinds and shit head on in rushes. Let the su85 deal with tanks.
And seeing as how conscript starts have a small capping advantage early game unless they go fast 2nd pioneer, I've found it to pay off to rush obvious buildings and stuff at the beginning to avoid the first mg42 to get into a very good position.