Quite frankly, Melo is a good individual player, but San Antonio (and OK city) are showing that the next decade belongs to team basketball. Melo does not make the players around him better. Lebron does.
Melo to Miami is plain silly, but hey, why not? The great players would never have gone for that... they wanted to beat the best of the best (i.e., compete), not just compile stats. Does anyone honestly believe that Larry Bird, Magic Johnson and MJ would have worked something out to play together on a team to get a ring? No way... they wanted to get a ring by beating the best, not co-opting the best.
Lebron would do well at Chicago or in Cleveland. Everywhere he goes, they'll be competitive for a championship. I love MJ, but Lebron may be better in terms of all the different tools and how he dominates the floor.