Interesting the title of the thread is rebuild but you chose to say retool, they are different. The Bills did retool but that does not have to come with decreased expectations.
I felt they had about the same chance as the previous 4 years of winning the SB but I would stop short of saying it is a SB winning team, they have NEVER been that. The big changes were over hyped...Poyer and Hyde were old and slow, Morse was replaceable, Davis was replaceable. The big loss was Diggs but I am not like most who dwell on WR's all the time, the Chiefs have shown that. I feel the Bills have an organization and QB to compete year in and year out, lots of the other pieces can change but they will still be able to compete for a championship. And they accomplish that by having good depth and they teach their schemes well. That does not mean there is not growing pains with some of the changes, but that is manageable for the most part.