This sub-task is to help resolve the "More than 25 groups" issue.
There are several things that could be done than to just up the number of groups. Looking over the list of comments, one prevailing feature is the ability to set prims. A ban/allow list can help resolve that just to allow people to set prims but without all the rest of the group features.
There have been ban/allow lists suggestion to attach the list to the parcel itself, but that would be harder because parcel line change too often that it would make the list(s) harder to manage.
This issue proposes one ban/allow list for each group that just grants or denies rights on an individual basis to set prims on land. In order for the ban/allow list to be effective, the land must, ideally, be set as group owned (or possibly just have group set if not deeded).
As a second hand feature to this issue: A bit of automation can be added to the ban/allow list such that as people are invited to the list that they automatically get added to the ban/allow list to set prims. Also, as they get ejected from group, they get automatically removed from the ban/allow list. Those that join the group from "open enrollment" do not automatically get added to the list. However, one does not need to be a member of the group in order to be on the ban/allow list.
The key point is that one does not need to be a member of the group in order to be on the ban/allow list. This helps resolve the issue of "more than 25 groups" by the use of a ban/allow list such that individuals can still set prims without the need of an extra group.
One caveat to this is that without being in group then there is no easy way to set a prim to group. There would be a need to change the "auto-return" feature so that it checks the ban/allow list and not just if prims are set to group.
Note: This issue is part VWR and part SVC.