Personally, the player I would like Vlade to target is Paul George, particularly if we don't pick Doncic.
He's one of the best players at the position we are weakest at, is old and accomplished enough to be the leader of a young team, and young enough to grow with the team for several years. If Fox and this year's pick develop into all star level players, with George, we'll have 3 potential all stars on the rosters. Add a smattering of other players, Bogie, Buddy, Giles (another potential stud, if the FO is to be believed), Mason, one or both of Skal/Papa, and we might have the tools to compete for years.
I purposely didn't include Willie. I don't think George (or any other tier 1 FA) signs with us this year (cap space will also be a factor. We might be able to create it, but costs could be high). We'll need to acquire him via trade. If he feels we have a better shot going forward, he might be willing to come over. If so, we'll need to give up Willie (and likely more, but we can give them some relief, if we can trade Hill's contract, which has a low buyout, so hopefully not too much more).
Pretty big leap of faith to suggest a player leave a team currently with 31 wins to join a team currently at 17. I do think though that the Thunder need at least one other major player to compete with GSW and Rockets, but lack the assets to acquire them. If the dominos (ping pong balls really) fall correctly for us, and we don't screw up, we could have one of the more promising futures in the league, something that will be attractive to FAs.