Dave, has your institution implemented
Delegated Access?
This way, you don't need to enroll people into each class. They can use the Delegated Access process to access the classes they need to work on, etc. Of course, if there are specific sites that someone wants to be listed in (as a roster member), then that's another story.
Our instructional designers and support staff in the past used Delegate Access to save them from manual enrollments into hundreds of sites. It also improved their user experience and reduced system load (we were on Sakai 22 and earlier, so large "Sites" menus ate up resources loading pages, etc.). Plus, folks would receive faculty announcements if enrolled and that wasn't desirable for people just designing or helping sites, etc. Teams would often use a Google Sheet with a list of all the sites for a given to work on, with direct links listed for easy access. The spreadsheets also communicated who was assigned each site and the status... Not Started, In Progress, A11Y Check, Complete, etc.
Now... to reiterate, we used Delegate Access in Sakai 22 and earlier. I am not sure how the tool works in 23 and beyond. I uncluded the Sakai 25 link above, so hopefully it's accurate for the current implementation.
Anyway... just an idea!
-- Alan