I would really consider moving Harden. He is extremely talented, but the Thunder are looking at the luxury tax. That's not the old luxury tax either but a much harsher one.
They can get more for Harden then Serge at the moment. Beal could be a nice replacement and fit at small contract for the next four years. I mean Harden isn't key to the Thunder's success.
The interesting thing for me would be to move number 2 to Portland for 6 and 11. You could potentially be looking at a Drummond and Lamb combo. Or Austin Rivers and Drummond. There are guys in this draft who while not as talented as Harden could definitely play his role as Super Sub next year. Waiters, Lamb, and Rivers could all fit in there and one should be available at 11.
At six you are getting one of Barnes, Drummond, Robinson, MKG, or Beal. All of those guys are in the same tier in my opinion.
In moving Harden you can definitely keep Serge and Perk, but also add 1-2 very talented lottery players on rookie deals.
Rich Cho, Charlotte's GM, was Presti's assistant GM two years ago so the relationship is there for discussions to become very serious.