I am a big fan of Zaccardo, and I think he'd benefit from a change of environment. I think he's around the same skill level as Zebina with the potential to be better, but a definite upgrade on Grygera. He's a monster than can pass when on his game.
My issue is Molinaro though. We'd be loading up the right side and leaving a true weaklink on the left. Unless the plan is to return Chiellini to LB (which may not be wise). Can Zebina or Grygera play LB, cause I'm quite sure Zaccardo can't.