We have a different situation depending on the draft position we get, and while we don't know what that is now, we will know prior to any move.
Our weakest positions currently are the four and five. Signing Durant would mean he would take 35 minutes at the three.
Out of the draftee possibilities, I would think Simmons could become an exciting complement to Durant, so if we get a shot at him, I would hope we just keep him. Simmons would provide a major talent upgrade right away at the four, and playing with Isaiah, Bradley and Durant would make things easy for him. He would make us better immediately.
Ingram can becoming a great player too, but he is incompatible with a Durant signing, so he would need to be traded if we got him.
Bender might work positionally, but it probably isn't great to have rail thin starters at the three and four.
All the other likely possibilities would have to take minutes from a pretty good player, and would likely require an additional trade of Bradley, Smart and/or Crowder to work.
So to me, we get Simmons or its best we trade the pick.