I would have tried to take Moscow, because of the impact it may have had on Stalin’s leadership. I don’t think it’s beyond the realm of possibility that Stalin may very well have been deposed had Moscow fell. And perhaps his replacement, realizing he needed all Russians to fight would have dropped Bolshevism.
Fact is, everyone with a hint of strategic acumen knew it was a nation of 70 million versus a nation of 170 million, the latter having unreachable industrial resources and the advantage of interior lines, a middleweight versus a heavyweight. The former had better win fast, and he didn't.