To me, Jaylen's ceiling is 23-25 PPG scorer, and a guy who can rack 5-6 assists and 7-8 rebounds a game. But best of all, he will also be an ELITE two-way player.
Sort of like Jimmy Butler except with slightly better 3 pt. shooting and more athleticism, if that makes sense.
As for his likelihood for making an All Star game this year, I think as of now, he won't, but if he can increase his scoring average a tick, up to 18-20 PPG, and maintain his 7 rebounds/game, he has a decent shot.