If you have the time, join more than one! I'm going to be checking out a quilt guild next month and wouldn't rule out joining more than one even though until I retire my time is a bit limited.
I also don't like groups that "require" certain participation. I was part of a wearable arts group back in the day that "required" that you did their challenge every year. I don't particularly like challenges and don't want to spend my limit sewing time doing them and eventually quit because of that.