Given the logistical nightmare that the USSR proved to be, I don't think an extra 10 divsions would have made a difference. He bit off more than he could chew, and then ran his army ragged by continuously shifting the goal posts.
Even if he'd taken Moscow, Stalingrad and Leningrad and pushes the Russians back to the Urals, the outcome (imo) would have been the same. It just would have taken longer.