Predictably, I'll go with Bradford. I've seen everything I need to see from him, but he has to put it together for the whole year including staying healthy.
But along the "whole team" line of thinking, the Rams are so young and loaded with high upside RGIII bounty players, it feels like a lot of players WILL step up just as a matter of course: Brockers, Jenkins, TruJo, Quick, Austin, Ogletree, Stacy, TJ McD. AND a bunch of the rookies really seem like they have the potential to have immediate impact: Robinson, Donald, Joyner, Mason. Langford found his stride mid-2013. Saffold found his true calling. Bailey looks poised to have a breakout year. Givens and Pettis and Cook should be improved with Bradford back. Even role players are ascending: Harkey, McLeod, Ray-Ray, Barksdale. Shockingly, BPOT Quinn is still ascending; only 23 last year, he'll be ascending for the next 3 years. And the entire D should be improved with Gregg Williams putting it together. This just feels like the first year in a very long time where we KNOW the team's identity AND that the Rams have the ability to win that way.
But the player who really has to make the difference between this being a team which is simply entertaining and competitive team versus a team that is "awesome", that has to be Bradford.