It is already in the Dev Kit to have a Musician thrall. Suggestion: Thrall musicians and placeable food! Personally, I think it would be an excellent addition to an AI Overhaul for NPC's, and would greatly help the atmosphere. I asked about this on stream about a month ago and they replied that they needed to work on music for it to be implemented.
I have seen other games use an MML Music program that allowed players to write their own songs to be used on in game instruments. While not necessary, it would definitely be a nice system to go with so that modders could easily edit/add in music.