I think music for the whole Age would get annoying after a while.
Environment sounds are important though. My ex-GF does that for movies, I can ask her for something if needed.
What would be great is if each shell had a short piece of music triggered when you enter it, and an ambient sound defining the atmosphere of the shell.
To Aloys' ISP: thanks, it worked great. The check is in the mail. Let's do it again next week.