I would trade Melo for a unprotected second round pick and a trade exception. I'm serious. He's that bad. We could easily fill his 18m with solid role players and draft picks that on a net basis would make the team better.
There is a huge difference between talent and playing basketball well.
Melo is an terrific basketball talent, but he's a terrible basketball player.
Some aspects of basketball are obvious, but offense is not.
The key to offense is NOT how many points you score or the degree of difficultly of the shots you are capable of making late in the shot clock.
The key to offense is knowing what your strengths are, staying with those, and not turning the ball over. It's about scoring efficiency, moving the ball when you don't have a great look, and not doing dumb things that lead to TOs.
Melo is terrible at all those things.
He's incapable of changing and becoming a good basketball player because he lacks the basic BBall intelligence to understand how to play the game properly and has an ego that's too big to allow him to listen to those that try to make him better (just ask George Karl).
Right now Gallo is already a better and more productive player than Melo even up. He may not be as talented and may not be able to do some of the things Melo can, but he's knows what he's good at (going to the basket to getting to FT line, open 3s, and scoring in transition) and sticks with it. That's why his TS% is a whopping 60+% and he doesn't turn the ball over much. Compare that to Melo's below average 52% and TO machine playing style.