I like a bracket match idea, with so many from each tier being allowed to play against each other based on the number of members the CC has.
Say each club is allowed 1-? members to play from each tier, depending on the size of the CC, but if only part of them actually play, you are losing points. This might cause CC's to expand, and to have new, lesser experienced players in their CC, and not be so exclusive.
Perhaps have a 12 hr clock on it for each match, allowing for 4 matches on a given weekend. Even having a different player playing and just advancing the CC not the player, allowing more to play each weekend, only allowing one player to play a selected number of times bases on the CC size in each tier.
But the prizes, some countries and states don't allow it, that might be tricky.