Both Curry and Harden are miles better at involving their teammates and running an offense. Curry is also not as bad on defense as always made out, he is shit in 1on1 situations but a decent team defender.
Have to agree with Sarni that although he has a great skillset I'm very wary of Booker's value on a contending team. The positive thing about him is that his efficiency has constantly gone up since in the league with a very good TS% now at over 58.
I feel like Booker would be a good 2nd or 3rd option on a contending team, let him do more catch and shoot which he's great with, make him a facilitator on some offensive plays. Just don't make him the focal point of your team because you are not winning if you do.
Ayton has the potential to be a great scorer and is not as bad on defense as he was supposed to be. If they get Ja or Zion in the draft, they might be able to build something out of that trio, I just don't think Booker can be their best player when they are winning.