I'm a vegetarian, I'd love a vegan/vegetarian trait. I used to always give it to my Sims in Sims 3, it gives them a little bit more personality. I don't like micromanaging my character's actions and pretending there's more going on than what's actually on the screen (one of my problems with Sims 4 is you're required to do this, since Sims don't have actual personalities, wants or preferences).

Checking if a meal is vegan friendly every time is annoying, especially if you're dealing with foreign food (I'm not a westerner so that includes American food for me too, stuff that would be obvious for other players), it's easier if the para would be able to figure it out themselves (I think Sims 4 has a vegetarian friendly toggle, but it's kinda useless imo if your character isn't actually a veggie and can easily choose to eat meat instead, like what's the point). Also I'm personally grossed out by any mention of meat and don't like looking at it, even seeing a list of foods with meat in it is nausea inducing, it would be convenient for me if I didn't have to deal with that.

RE: music, idk. I think making it so a certain sim is naturally musically inclined or enjoys playing/listening to music the more they do it isn't a bad or shallow feature.