Really hope he reconsiders, because otherwise he's probably getting shipped out of town. Selfishly, I'd love to see Waiters get the chance to play with LeBron. He makes everyone better, and Dion could still turn himself into a pretty good player on a great team (never going to be a franchise guy, but still ...).
I also think the 6th man role would be absolutely perfect for him (this all assumes the Cavs don't trade for Kevin Love, which either would include Waiters, Wiggins, or both). If he comes off the bench he can lead the second unit, and still play a ton of minutes, just like at Cuse. He'd also spend less time on the court with Irving, who isn't a great fit for his style, and provide another scoring option with LeBron when lesser players are on the court.
Dion just doesn't have a real sense of his value. He's not better than Irving, so he's not your starting point guard. LeBron doesn't need him as his second banana at SG because all Waiters is going to do is drive (he'd be way better off with a shooter at the 2). And he has nowhere near the potential of Wiggins.
Maybe he just wants to get out of town, but if I were him I would consider how valuable you could make yourself as the spark plug sixth man on the best team in the world. Even if your goal was about maximizing value over championships, that's still probably the best way to do it.