Carter is clearly a good defender, when properly motivated. He was infinitely better than RJ last season.
A couple of comments: top to bottom, this will be a better defensive squad than last year. In recent games, the off-season veteran acquisitions have all been injured--some, like Najera, will be strong defensive presences. This, in turn, has forced players like Gill, Ager, Hodge, etc. to play more minutes than they will in the regular season (Ager hasn't been bad, though). Carter, also, has played roughly ten to 15 minutes per game fewer than he will in the regular season.
Also, BOONE hasn't been able to play. Don't think that hasn't made a difference.
This team will be very erratic for the first six weeks. The question is how they will hold up emotionally. If they can keep their focus, and keep their confidence up, they will start to play better in mid December, and I think can stil achieve 35-40 wins. I am pencilling them in for 39, in part because I think they are very deep, and they should be able to withstand the normal amount of injuries better than some of the other teams they will be competing against (other than Vince, of course).