Bonucci did not fulfill his expectations and his price of 15mln euros. I do like him, but he did not show much and he was fragile many times, especially when he's left out alone. I do think he needs time to settle, just like Silva needed it. But I don't think two giants like Chiellini and himself will ever be able to make a positive duo.
As for your opinion about Ziegler, I'll leave it at that. To say he's spectacular is enough for me to avoid any discussion whatsoever about him. Not that you're biased, but I can't believe with my own eyes what you're typing.