Mark-- If your goal is to induce some order on the suggestion process, i.e. consolidate duplicate or similar ideas, reduce the number of suggestions that have been hashed through in the past, and generally vet suggestions before you look at them, I suggest that you appoint a volunteer board to review the contents of this group, beta, and create a list of processed suggestions. Let beta remain the free-for-all that it is, but assign some volunteers to do the preliminary work of preparing proposals to enter your work queue. I would strictly limit the suggestion analysis board to vetting suggestions from the beta group and prohibit the board from making suggestions themselves to avoid abuse of the boards privileged position.
A suggestion analysis board could work in different ways. One way would be a group or a beta subgroup moderated by the board and only board members could post. Suggestions would still be posted to the beta group, but the suggestion tag would become a flag that the suggestion board needs to scrutinize the post and consider it in their group. Then periodically, the board would post a vetted suggestion list, similar to your weekly change list, to the beta group.
You, Mark, would remain the ultimate arbiter of what gets done, and discussion in beta would not change, but you would have the benefit of the work done by the suggestion analysis board. I would keep the deliberations of the suggestion board public, although I would expect it to be pretty boring because it would not be a forum for new ideas, just sorting out the beta discussions.
BTW, just to be clear, I'm not interested in a position on such a board, but I would not be surprised if you had a few volunteers, based on the great work done by the thankless moderators of the Group Management Forum.