I ran a private online bookclub a few years ago, really tried to filter and vet the people who wanted to join. Ended up with a decently sized group of wonderful people and lots of long form written discussion—we read good books and talked about good books, it was lovely. I approached the screening/vetting process as if I was hiring. I got some angry emails about the approach, made it seem "exclusive" and elitist, but it worked out well for the group.

I'll launch the next iteration after the first of the year, this time there might be a fee attached, at least a minimal amount to pay for the SaaS product we'll use to organize and collaborate.