The only reason Russia defeated Germany on the Eastern Front is because Hitler chose to fight on multiple fronts. Had he chosen to concentrate his forces we would have a different history today. The Red Army was bad then, and it's bad now.
Sure, but remember, "good" and "bad" are strictly relative terms -- good means you are better than your enemy, bad means he can beat you in a fight.
Whenever the German army could concentrate enough forces in a schwerpunkt, they could beat the Soviets, or anyone else. But even in early 1943, the best German general (Manstein) with all possible backing from Hitler could not concentrate enough forces to break through and relieve Sixth Army at Stalingrad.
That tells me the Soviets, even then, had gone from bad to good, and the Germans were quickly becoming pathetic.