I really don't know. On one hand, Melo seems like one of the best players in the game. On the other hand, he's been surrounded by talent most of his career and has done very, very little with it. If he's really a #1 guy, he should've gone a lot further in the playoffs than he's gone at this point.
Still, Rondo has been surrounded by top notch talent over the the past few years, so perhaps things are a bit inflated. So it's tough.
I might do it only because Melo is perceived to be a superstar by other players and could be helpful in landing another big time free agent. For instance, if the C's pulled the deal today and Pierce walked tomorrow, they might actually be able to persuade a LeBron or D-Wade type to come to join Melo.