How do you managed to get outblobbed while playing as soviets? 
you have a lot of options, but either go t1 penals, t2/conscrip combo or just plain olde conscript spam until you get 2CP and then just get a couple of shock troops to completely dominate the infantry battles.
If you go shock rifle both t3 and t4 are entirely optional as you can just hold of until the IS2 (though I would recommend getting at least t3).
manpower bleed when using cons or more expensive units (plus inability to build cover) when using penals, I still find mixed arms best as Soviets, maxim first, two cons then another maxim, then a con, after that get guards or shocks, depending on commander choice, also don't split your forces too much.