It's going to be tough to find a contender who will want to build around Westbrook.
Do you want him as your #1 option, when he's shooting in the low 40s while turning the ball over a bunch and making awful decisions down the stretch and can't hit a game-winner to save his life?
Or do you want him as the #2 option when his low bball IQ and extreme confidence guarantees that he'll be taking shots from your #1 player?
He's a huge talent, but he's not efficient and doesn't play well with others. The two OKC teams he got far on were insane stacked, with Durant-Harden-Ibaka-Thabo on one and Durant-Ibaka-Adams-Kanter on the other. Not many teams are going to have an MVP and a bunch of talent around him AND enough trade value on top of that to get Westbrook, and will still actually want him.
I see almost anyone winning a ring before Westbrook does. Until his game drops to the point where he's a clear #2 and accepts it, he's not going to be title-winning material.