If Splitter makes it known that his intentions are to make the transition to the NBA, I would try to avoid including him in such a proposed deal. And if they insisted on Splitter, I'd turn them down. Splitter is as just as valuable as any big man in the draft except a lot more polished and ready to contribute IMO. It's hard to come by a skilled 7 footer like Splitter in the first place, which only makes his value that much higher (if he is coming over this upcoming season).
Of course some big men in the draft might have a higher ceiling (Favors), but he would be just as valuable as Splitter these next 2-3 years. Spurs downgrading to Devin Harris and then making a sideways move at least for the next 2 years by trading Splitter for Favors (if Splitter comes over) doesn't improve the Spurs.IMO
When it comes down to it, I don't think Thorn agrees to the deal unless Parker agrees to sign for the long-term. At the same time I don't think Parker signs for the long-term, unless a big name free agent signs there anytime after July 8th. Which makes the trade very unlikely because the trade would have to happen before free agency.
But if we are playing the trade scenario game, I'd be willing to part with Parker, Blair and/or #20 and the rights to Colo.