The thing about expiring contracts is that their value to a team (or another team) is limited to the following situations:
A team that wants to dump a bad contract, or
A team looking to dump a good, but highly paid player to go in another direction.
No reason for Orlando to take a bad contract (on top of the ones they already have), and the # of teams looking to dump good players are pretty small. [sidebar: we got incredibly lucky in 2007]
Iggy is the only name that comes to mind, but his lack of outside shooting makes him undesirable in Orlando.
Rashard "worst contract besides Hedo" Lewis might be a decent deal. The Wiz have shown a lack of depth at SF and could start him there (ahead of Al Thornton). His shooting might open things up a bit for Wall. I'd want a sweetener if I were taking on Arenas, though.
That's the deal: Arenas and a pick for Rashard. Vince goes elsewhere or expires. Nelson/Arenas/Vince guard rotation this year.
Another idea: Vince, Gortat, and 1st round pick from WAS as elements of a Melo deal. Nelson/Arenas/Melo/Bass/Howard starting. Reddick keeps his job. Denver likes big guys, get pick and Vince's expiring.
Arenas/Melo are tougher mentally than Vince/Rashard. They both play up to the moment, which is what the Magic are missing.