If Japan AI and National China AI do not declare war on Russia, which most likely would happen, Russian AI would have nothing to worry about on the East. If you played Axes (not Germany), you would have Japan or yourself to attack Russia's East coast (about 30ICs or so at least). And Russians "should" fall. But the Russian AI mostly manages to rush through Romania for a counter attack...
If you are Allies, you would have worked on Germany's West side to recover France while Russia draws ~70% of the fire from Germany. Russia mostly would not fall if you work practically.
If you are Turkey (some how

), you can join Russia and help out abit for the Romania part. Alternatively, you can join Axes attack Persa and weaken the Stalingrad abit. You can also join the Allies, and open the route for Russia's Romania-entry
I can't see much about the "unbalance" part, the "human factor" can alter the result a lot. May be just that you did not help Russian for the 2 years...