something like a combination of clans and tournaments.
RHP creates a World Cup Tournament. They ask all the members if they want to join in the world cup. Once they then know whether everybody wants to play in this tournament, they create 'clans' of ten players of the same country in each clan - according to rating - so the best ten in the first clan, the next ten in the next clan, etc. All these clans then compete against other countries' similarly rated clans - i.e. clan 1 of my country plays against all other clan 1 of all other countries enrolled in the tournament. so also clan rated 2 against the other clan rated 2 of other countries. and so forth.
don't know what to do about the fact that some countries will have more players than others. maybe each clan level should have its own world cup?