With all those other SW movies Disney wants to make, I imagine they will be offered to some of those people they couldn't get, or didn't want the job.

Nobody wants to be the guy who screwed up Star Wars. Most people won't recall who made John Carter, but make a bad Star Wars sequel, and even M. Night Shyamalan won't want to be seen in public with you.

Once the sequel is out, and hopefully it's good, more directors will want to play in George's sandbox without the heavy burden of reigniting the franchise.