Buffalo's non-QB needs

The Buffalo Bills decided that no matter what they do with their player personnel this offseason, they needed to alter their coaching staff to get the most out of whoever was on the field this upcoming season. We know that the QB position is one that will be addressed to some degree -- whether or not Ryan Fitzpatrick is the starter in 2013, he's the only one currently under contract, so they'll need to find some help -- but what are some other needs?