With his bird rights and RFA, and the fact that he should be 100% healthy (and the fact that he can sit on the end of the bench and not play without causing problems) TA should be brought back.
C's only have so many avenues to get players in here, MLE, LLE, Bird Rights, Trades, Draft: TA is at least good enough to be on the bench and useful fill in, and he's effectively free (assuming the owners aren't worried about money.)
That being said: C's 100% should look to upgrade everywhere possible, while we fans are in love with the guys on the team, consolidating 10 5's into two 10's got us KG and RA. Consolidating a couple 3/4 bench players into a 6 would strengthen us. The competition won't rest on it's laurels, neither should the C's.