two words my friend
Bardic lich.
I really hope they make the bardic lich template for 3e soon, for completist sake if nothing else.
As for traps and obstacles you should make it so that the only way to get through a door is to sing a set of notes (make a performance check.)
You should also look for musical puns (like a sharp and b flat. If your pc fails the music roll they could either be crushed or cut.)
The dungoen would also be populated by musical monsters (such as destrachan, satyrs, sirens, harpies and even lillend.)
hope this helps.