I would even say that some of those who do not handle the authority issue well - Wesley and Faith, obviously in different ways - are only redeemed in AtS. They were noir characters in a non-noir universe. (I really can't find one word to describe the Buffy universe)

In the Buffyverse they are denied the right to really mature - they are simply seen as static entities. Moving to AtS opens their personal universes in some amazing ways. I know this was needed - Buffy had it's quota of characters to follow if nothing else.