limit offered albums by a tag..?

[simoncn]

As you say, the solution is to create a tag (choose any name for this) that can have one or more values representing the family members who want to view this music. For example, the tag could be named Person and the values of this tag could be John, Jane, Jack and Jill.

If you add Person as the first tag in indexTags, the top-level menu will show a Person choice with values John, Jane, Jack and Jill. If Jane is selected, the next menu will show just the files in Jane's library, and likewise for the other names. This scheme allows the same file to appear in multiple people's libraries with no need for duplicate copies of the file.