If Anthony Davis is quietly (yet understandably) upset and demanding a trade to a contender, it would be amazing to land him. I would give up anyone and anything, including Thomas. I would say there is a 0.1% chance of it being Davis, though. New Orleans owns him on that contract and he is THE guy under 25 (or perhaps Towns) you build a team around if you can pick anyone in the NBA today.
Griffin? I highly suspect the Clippers are all-in for a championship this year, so 0.1% chance again.
Butler? It seems obvious that he is going nowhere as the Bulls have just added Rondo and Wade, so they are looking to contend rather than rebuild. 1% chance since perhaps they are satisfied with replacing Butler with Bradley (I suspect Rondo and Wade think highly of Bradley).
Hayward? Utah has done a lot to make themselves contenders this year, so I would be surprised to see them ship him. 1% chance since he is on an expiring contract (and has possibly already made it clear that he is not likely to resign next year).
Cousins? I think he wants a trade. I think he is praying to get out of there and Sacramento has drafted enough centers the past two years. I think he is the most likely candidate, and he is certainly the one I am hoping for. 10% chance he is traded soon.
A couple other guys I would be thrilled with at the right price (I expect one or both to be all-stars in the near-future): Jusuf Nurkic or, preferably but quite unlikely, Nikola Jokic.
Khris Middleton would be nice at the right price (for example, Bradley and a non-Brooklyn pick).