I'm going to say Corey Vereen becomes a name every SEC team knows by mid season as a full time starter opposite Barnett.
I'll say Gaulden if you want a "newcomer", although we all know how talented he is.
D Taylor
Darren Kirkland Jr (unless you think that he has already broken out - he had 66 tackles last season which was 4th on the team)
Otherwise, how about Marquill Osborne?