Well, I consider Jeff Green and the Clippers Pick = to Kendrick Perkins right now. If we do this trade, we are losing Rajon Rondo and ~60% of Perkins for Westbrook.
I believe Rondo has more value with most teams in the NBA than Westbrook does. I'm not saying Rondo is a better player (Though he is), but in this trade, we shouldn't be the ones giving extra pieces. Imagine Westbrook in the Heat, Bulls, Celtics, Lakers, Magic, Thunder, Mavs, Etc. Then imagine Rondo on those teams. Rondo w/ OKC is better than Westbrook w/ OKC. Everyone is talking about how Howard and Rondo would be one of the greatest defensive duos ever, but what about Perkins and Ibaka? Then add Durant/Harden/Maynor in and that's multiple championships.
I'd lightly consider this trade if we were getting Ibaka, Harden, other players from different teams, etc. (While not trading Jeff Green)