Prince Kevin would be a good name.
I know a lot of Brit-Americans with that name. One of them is my friend, he works in Wall Street.
I think the Windsors stick with Anglicized Norman Conqueror names like William (Guillaume), Henry (Henri), Philip (Phillipe), Louis, etc.
Maybe they should go wild and name him Robert, Geoffrey (Geoffroi) or Francis (Francois).