A year or two as a backup with a good coaching staff willing to put some serious time into chipping away the rough could do wonders for him.
He would have had that in Denver, but they chose to jettison him instead of keeping him on as Peyton's backup. If anyone could train Tebow, it'd be Peyton. But the front office didn't see it that way; they're the ones who see him in practice every day, we just see the games. One can only assume that they had more faith in rookies than they did in Tebow.
Either that, or Denver cut him due to the pressure of the fans wanting to see Tebow, and didn't want that distraction for Peyton. Likewise with the Jets and Sanchez (although, Sanchez is probably on his way out now, too).