I am an artist, and a writer with about a million and a half little plot bunnies bouncing around in my head, interested in this jam but who has no idea how to program. So being able to help you is right up my ally! If you'll accept my help, I mean.
I have no experience with designing a game UI, but I'd be happy to at least try my hands at it! I've played enough visual novels to know how a visual novel UI should generally look, I think.
The only thing I'm unable to help with on your list at all would be music.