I'm thinking of doing something a little different with the writing group. For me it works fine: I set weekly goals and either meet them or don't (usually I do). I check in every week, except when I deliberately plan on not doing so when on vacation. I've made even more progress on my projects that I normally would have, and that is saying a lot because I was already a super-productive writer. A few others also check in every week and are doing well. Some, however, have not been heard from for a while.
So my plan is to figure out who has not posted in a few months and eliminate them, then invite new members to join. Thirdly, I'd like to set it up with more rigorous rules and perhaps a more formally defined set of interactions. I'm not sure what yet, so pardon my vagueness, but I think it has to be (and do) a little more than it is now.