About vetting potential members, there is the difficulty of do it, I mean, you do need a good player first meets with a recruiter by chance, and then it needs the recruiter notice him someway. Even if that makes a FC grow slowly, it surely have the benefit of reduce the potential for unwelcome guests.

Then, there is the "random shouts" method, that makes a fc grow with people that have asked to join, but you don't know who they are until they shows themselves into the fc's daily life.

A third one is halfway between them: the recuiter that chat with any fc-less players to check if the player may join, just checking the simple willing and/or common interests.

Will now try to update the op with your suggestions trying to be as neutral as possible, thanks!