@Monarkie thank you for your support, and everyone else, thank you for your positive reactions (or your silence). 
I think I have done everything, but please check:
- Members has an intro about the space, explaining that the content is unlisted but public, not private, and that anyone can share links publicly.
- Members > Our music has a README and it is muted by default. Music makers can create their topic.
- Members > Meeting points has a README and it is muted by default. Right now the only members who meet the requirements to create meeting points are @defaultmediatransmitter, @Mel, and @icaria36. The list will grow as we get regular members and more mods/admins. It is possible to request meeting points.
- Muting & unmuting, explained at Follow or mute topics, tags, and categories in TSMN
This is how Members looks right now when you unmute the subcategories:
Ok, let me know if you find any problems or you have any suggestions.
I’m going to create a Bandwagon meeting point and advertise it on my Mastodon account, because why not and as a test with a real topic.