Well, he has no trouble getting to the rim, which is huge, but his touch is terrible right now, and that's not something that's easily improved. If his hands develop (he's still young), look out.Favors because I feel like we are only seeing the tip of the iceburg.
I voted Favors, but I really like the promise of both Burks and Hayward.
It won't be popular, but I'm just not sure yet on Kanter. I see his best case scenario is as a Charles Oakley type career. He will have a long career and be a solid contributor, but I'm not sure he'll ever be more than a 10 point 8-10 rebound physical player. That is very solid, but not a star. However, I see star potential in all three others.
Edited to add a link to Charles Oakley's career stats - https://www.basketball-reference.com/players/o/oaklech01.html
I voted for Hayward as well, but you said it best. Hayward over the last couple of months has really impressed me. As much as I've liked that his shot is coming back and he's playing good overall offense, his defense is what has me the most excited. As far as Burks goes, I think he is going to be a star in this league as well.I voted Hayward but it really is a toss up for me between him and Burks. I am highly optimistic about all 4 though.