The Magic are screwed for the next few years, not matter what happens with Dwight. At best case scenario, they'll get a borderline all star and some picks.
Likely scenario is either Dwight walks, or they get a few solid starters/young guys and picks.
I say go for it. Lopez is deadly at times, offensively. He needs to step up in every other aspect of his game, though. Marshawn is a potential high scorer, and Humphries is all around solid.