In my opinion, Carter is one of those players that will forever be judged by issues other than his on-the-field performance, regardless of how far back in the rearview he leaves his problems (which he admittedly hasn't even begun to do, apparently).
The first strike against him came from his draft position, which he obviously had nothing to do with.
The kid has had a lot of stuff exposed about him in the last year, and he's definitely still got business to take care of. However, he has an above-average arm and mobility, and by all accounts is a diligent worker/student of the game. Parcells himself praised him often leading up to Cowboys TC 2004 (right before the marijuana issue came out) for all the work he'd put in during the offseason, often staying at Valley Ranch for up to 10 hours a day working out and watching film.
Whether he'd be appreciably better than our top 2 right now is too close to call however.