From: Cameron, Missouri
IMHO, if the Russians are played competently, the Barbarossa scenario is quite difficult for the Germans to win. Bad weather luck makes it very difficult.
Obviously I am very new, but as a learn the system I believe you are correct. Yes, the Germans can take the North and surround Leningrad, but then it can be setup as a bulwark and made extremely difficult for the Germans to crack.
The South, from Odessa to the Prepit Marshes can be made pretty much one single line. Yes, the Germans will make breakthroughs here and there, but by withdrawing units the USSR can set it so that the Germans have to slug there way through.
As far as the middle road, towards Moscow, yes the Germans will make big advances, but if the USSR player concentrates on building land units they can set a wall around Moscow that will stop the Germans.