All of them can, for different reasons.
I think Andrew Luck will be better, but statically it may not show up. That's because the Colts completed a very high number of very low success throws, which is more likely from luck, not Luck. Although he may continue to live up to his name, so it's hard to say.
I think that more defenses being able to study all the read option guys is going to hurt them as well, and they may have down years in terms of wins, and other stats. Some will go up some will go down, but I don't know if any of them are going to be as good as last year.
Don't tell the media that though, because they will still shove them in everyone's face for the ratings.