I don't think Deron's available just yet, and I think Rondo for Westbrook's a pretty big gamble. Rondo's locked up on a pretty friendly contract. Westbrook's about to be an RFA and will likely command the max by virtue of his scoring averages.
I can see the argument for Westbrook - bigger, younger, stronger, more potential to improve his shot, more scoring ability - but I don't find it compelling enough to pull the trigger.