Don't know how high he will go, but, his stats indicate the arc continuing. I beefed about him playing with Popovich this summer, but, i think experiences like that help a young player.
Assists to me reveal a great deal about maturity and commitment to the team. Good players know what they can do and also, what they can't. There are plenty of top players who achieved little in the NBA beyond putting up stats....Tatum can ask Kemba how rewarding that is.
Three year assist totals (1st) 128 - (2nd) 168 - 233 (pjctd this season)
Three year steal totals (1st) 83 -- (2nd) 84 -- 112 (prjctd this season)
Playing on defense is what great stars do probably because good defense wins titles.
Kemba has played his butt off on defense and I'm sure that example has helped everyone else including Tatum.
It is interesting how Stevens has given Tatum the "ball with the bench". He is still ball dominant with the bench, but, his game has improved.