If we get Kuffor, then we don't need Miha and Matrix. Miha might be happy with a marginal role, but Materazzi may believe he can still be a no.1 defender somewhere.
If we let Davids go, then we don't need anybody. I believe that a midfield arsenal of CZ/Cambiasso/Stan/Kara/Veron or Pizarro, is more than enough.
Why are many people turning on VDM? He is starting to play well, but this injury came at an unfortunate time for him. He was starting to adapt to Serie A, and he had some awesome performances, we don't need Taddei whatsoever.