Here's a list of the remaining FA QBs. I would have to think that some (if not all) of them should be brought in for try outs. I don't know how that would work with the cap though.
http://www.spotrac.com/nfl/free-agents/quarterback/available/
Is there any undrafted rookie QBs from this year that they can bring in?
Orton and Campbell are there because they retired. Cross them out, and do you really think Lindley or Jordan Palmer would add any clarity in Buffalo?That leaves the only intriguing name on the list as Michael Vick...whether that option is attractive likely depends on how you viewed his "not ready to play, just wanted to hold a clipboard and collect paychecks" attitude from when he last held a job. Would bringing him in as a starter be enough for him to give you everything left in his tank? And what does he have left...
Pretty rare these days when a starter-worthy QB is available for free. Maybe they should be looking to trade for Glennon, Mettenberger, Cousins, or your favorite second stringer elsewhere. Would that be any better than Taylor though...