I've always wondered if it would be feasible to arrange a sort of speed dating system to help build groups. There would be a single system and GMs would be arranged with small groups using pregen characters to run a small event with a little bit of everything in it to help give the GM an idea of each player. each player after an encounter would vote yes or no on the GM. The GM would vote the same and any matches would be used to suggest a group of whatever size the GM wishes to run.
