I also think it'd be cool (though probably buggy and impossible with existing games) if they removed "vegetarian" as a trait and instead added "dietary choice/restrictions" to the info panel like the gender stuff.
And by default sims eat whatever, but if you want you can go in and customize it one-by-one and check off whether they can have like
Meat
- fish
- beef
- pork
- poultry
- fish
- shellfish
Animal Products
- dairy
- eggs
- honey
Beverages
- milk
- coffee
- tea
- fruit juice
- "juice" (alcohol)
Other
- gluten / wheat
- processed sugar
And maybe also a list of specific produce.
And then you can decide what your sim eats on the basis of anything. And it's not labeled so it's up to you if they are refraining for personal or religious reasons or if it's a health thing or what. Create your Hindu sim or your Mormon sim your diabetic or celiac's sim at your discretion.
Basically we need a more robust Info panel, so we aren't wasting things on traits. And if we were updating the info panel anyway, you could then add the options for new walkstyles (adding canes - both walking aid cane walkstyle and seeing aid walkstyle, and wheelchairs), and options of how the sims talks (with voice or hands or both), how sims talk to them, how they read (with eyes or hands), if/how they watch tv or use the radio, how they write/do homework, etc.
It is true that it would involve a lot of new animations. It's not impossible but it's a lot of money to spend making something they couldn't ethically charge for. I'm not counting on it, but I do think it'd be a great addition to CAS.