I think, it would be nice addition to have the option of a second root for the browser tree. You could use the first root for all the "official" qlr files (and making the directory behind it read-only) and have a "personal" root (where you have write access) to contain all your "personal" qlr-files.
I've been experimenting with having either symlinks or shortcuts in the directory used for the qlr browser, but the methods are not stable enough for everyday use.