I agree that Lelouch is the king because he doesn't really do all that much in battle itself. I'm not so keen on C.C. being the queen, because unlike Kallen, she hasn't actually gone out there and done much. But I do agree that the Order of Black Knights essentially makes up Lelouch's pawns.
I considered Cornelia as queen, but given that she seems to be part of a two-person 'set' for Lelouch to conquer, and that Suzaku is winding up as the more powerful fighter, I'd make Cornelia (and Schneizel) a rook and Suzaku the queen. I'd also definitely stick with Jeremiah and Viletta being knights.
(no subject)
I considered Cornelia as queen, but given that she seems to be part of a two-person 'set' for Lelouch to conquer, and that Suzaku is winding up as the more powerful fighter, I'd make Cornelia (and Schneizel) a rook and Suzaku the queen. I'd also definitely stick with Jeremiah and Viletta being knights.
But yes, knights = horses, rooks = castles.