I agree with crusaderiv about not having Soviet troops fighting alongside Western Allies troops. Except for the supply convoys from USA to Russia and Lend-Lease equipment, there was little to no collaberation between Soviet and Allied troops.
I don’t agree with allowing USSR to destroy their own facilities at no cost at all, or ANY nation for that matter, Axis or Allies. I think a good way to do it would be to use your defending infantry to cause damage to your facilities. For each damage point you want to inflict on your factory, 1 defending infantry unit DOES NOT get a defense roll. They can still take hits, they just don’t fire back at the attacking forces. For example: Say you have 20 infantry defending a Minor Industrial Complex and you get attacked by a large force so you think you will lose the fight. You want to max out the damage on your Minor IC (6 damage points). So, you sacrifice 6 defensive rolls to max out the damage on the IC and only roll 14 dice instead of 20 on the FIRST ROUND of combat. Now say the attacker got ONLY 6 hits, you can take the 6 infantry that didn’t fire back as casualties. If, by chance, the attacker got LESS than 6 hits, the rest of your infantry would defend as normal. The IC sabotage penalty applies ONLY to the FIRST ROUND of combat.