Cleveland's best path forward is to keep Lebron James. He's the best basketball player in the world and his departure will crush that team. If they lose LBJ and IT, CLE will be bad enough to get their own draft pick similar to the BKN pick. They should not prioritize picks right now. They should prioritize Lebron.
I'd ask him what player he wants to play with, and trade whatever to get that guy. The problem is the top 15 players most likely aren't on the move. They don't have the capital to get Anthony Davis. I don't see OKC sabotaging a playoff run by trading PG13.
Going down the list of top players, I think Rudy Gobert, Demarcus Cousins, Deandre Jordan, and Hassan Whiteside might be their best chances to improve, though I'm not certain the Nets pick acquires all of these guys.
Lebron coming back to CLE was a good story. I think his best path forward from a PR perspective (you know he cares about this) would be to stay while CLE improves quickly. This means experienced talent, not 19 year old draft picks.