Twoish mil per year overpay is one player on the end of the bench, like the tenth guy. Not a big loss. Enough has been said about his value, and I think he may just be worth it right now if he can handle starter minutes.
Someone mentioned that he needs a point guard. I fully agree. Most everyone agrees that Al needed to go, but now we are wanting Favors to play the same as Al did, namely post up and have some unstoppable post move. He's not that guy, he's a mover who could be much more dangerous if a point guard can get him the ball in the right spot. I believe that Favors best offensive ability is to get the ball on the move and blast it to the hoop. In fact that is what he said isn't it? That he wanted to have offence in the flow of the game? We already have a post anchor in Kanter, we don't need two, and the less those two imitate each other, the better we will be. He does need to develop his shot more to keep his defender up close so he can blow by, but that can be learned. I think he needs to be himself, and if he is a superstar defender and a starting quality offensive player, he's worth more than he's getting.
Edit: concerning Favor's personality, Kanter is the loud noisy type, while favors is the reserved moody type. Another reason that it's ok to have them both, they probably compliment each other even on the personality front.