Tatum needs to work on his midrange and post game. He misses short when he does his fadeaway as a counter after driving, just seems like he doesn't have the strength yet to make that shot consistently yet.
Too much of his plan of attack is off the dribble 3s or layups, everything in between is weak imo. He's 6'10 he needs to study how KD creates space and hits the midrange jumper when he's off-ball and how DeRozan does it with the ball.
I mention DeRozan because he initiates offense a ton and still gets to his spots and is damn near automatic when he rises up. Tatum is taller, so even if his handle isn't as nice as DeMar's he's gotta figure out how to use his size to get easier looks.