Firing Mayo won't look bad for anything, except Kraft's ability to hire talent with his emotions. Which is to say, that's everything for a guy trying to cement his HoF legacy. But, if he's not willing to concede a short-term mistake now, this team will flounder for the rest of his decision-making days, which is to say, hopefully not much longer.
If he can land Vrabel - the fan base will be ecstatic, and resurgent with hope (again). They'll forgive the Mayo-disaster.
I'd honestly suggest keeping AVP - just for the continuity of Maye. But, fire DC, and fix this defense.