I don't think nationalities matter anymore.

The Voice AUS has a Brit, an American, a Puerto Rican and one Australian.

I thought Louis was leaving? I think he will be replaced by one of Westlife (not necessarily Shane although if his solo career does not take off perhaps he will come back as a permanent judge rather than at judges' houses).
Cowell really does have to get himself back over here if he wants to make the next series a success.