Davis sucks, but you need to sign a quality backup QB then if you cut Campbell.
And you have to re-sign or replace the following within a year or two
MLB + SLB
LG +C +RT
Outside of Melton and Cutler and maybe Wright, none of those guys are going to be re-signing at a large salary increase. You forgot to add Peppers to that list, he probably only has 2 years left in him. That list shows why its incredibly important to draft well in the NFL. They have to come out of next years draft with 2 starters in the first two rounds.