What terrible nondoctrinaly units are we talking about here? Apart from the SU-76 (and maybe the t34/76) every unit they can field is decent and they can have a lot of stuff on the field all the time, which many of you seem to forget.
T34/76
T-70
Su-76
SU-85
^These units are supposed to form the backbone of the soviet lategame. Not only can you not have access to all of them at the same time, but not one of them (with the exception of the T70), is performing up to its cost.
The T34/76 is too expensive for what it gives you. It is a decent tank, but it is not worth 310mp and 100fu.
The SU-76 needs no introduction.
The Su-85 works well, but it needs an accuracy buff. It has a hard time hitting targets that are moving, and does even worse on the move (rotation counts as movement in game).
If the T34/76 and the SU85 came together, they would make more sense, but as independent "top tier" units for the soviets, they are not nearly good enough.