That's pretty close to my view of things.
Isaac has gotten some Durant comparisons due to his build and skill set but while Isaac has a nice handle for his size and can shoot, Durant was elite in terms of quickness, agility, ballhandling and shooting for his size. Isaac is much more deliberate, lacks burst or explosiveness and his shot has some windup to it.
But I f Cousins was still on the team Isaac would be my pick. He can be a spot up shooter and is a good defender who offers rebounding and rim protection. Tatum wouldn't necessary help space the floor as well and needs the ball in his hands more.
Without Cousins the Kings need a go-to scorer. The risk with Tatum is that you're counting on him to be the main guy and star. If he's not then you get a Rudy Gay, Jabari Parker type - high volume, relatively low efficiency scorers who don't do much else. While they are very different players I thought it was interesting that Tatum's freshman stats match very, very closely with Paul George's sophomore year stats.
I don't see Isaac becoming a star. But I also have a hard time seeing him not be an effective player. With Tatum I don't see bust potential per se, but the important question is if he can be the best (or perhaps 2nd best) player on a good team. And I don't know the answer there.
But Tatum, Ntilikina (or Fox) in the 1st round and Jawun Evans in the 2nd round would be a draft I'd be happy with. They'd likely still struggle next season but two summers of smart FA signings and another likely lottery pick next draft and the team could finally be headed in the right direction.