I'm arguing that Blatt has experience and that it shouldn't be an argument. I honestly don't know how to judge Blatt or Kerr or Lue in terms of NBA coach. We saw that when Walton took over the team, they played even better than last season.
Obviously Blatt had a lot of adjustments to do, since NBA is so different. But I doubt Donovan has any advantage over him in that area or Kerr or now Lue. Yes, there are things they know better, as far as being in the NBA goes. But... Blatt has the advantage of knowing how to actually do coaching (just like Donovan) in crucial moments. Being a player or assistant coach doesn't prepare to a situation when the game is on the line and you need to make the call or things don't go your way and you must improvize and so on...
Also, I believe that Cleveland did the right thing, not waiting for Bron, regardless of whom they would have signed. Bron held the entire league hostage and it shouldn't be the case. Bron could have easily said to Cleveland that he wants to come back and they would have prepared accordingly. But he milked all the attention he could get...