The Bills have a good thing going on, and the best part is that it is very unlikely that Frazier or Daboll become head coaches. I see Daboll being like Greg Roman. Even with what Roman has done with both Kap and Lamar in designing unique offenses he isn't seen as a serious HC candidate.
There is nothing wrong with getting paid millions to be a successful coordinator on a winning team and gets pats on the back all the time and (hopefully) win titles together.