Thought of a few more things, not sure if they've already been mentioned but here goes;
Online dating app - I know there's mods for this but it would be cool if they added an app on the phone like trendi
Zodiac signs - Could tie in with the above, for compatibility. I also think it would be cool if you select the sims traits in CAS and it matches the most likely sign based on traits, like in the sims 2. Or you could select a zodiac sign of your choice and it gives a reward trait based on the zodiac sign, like Scorpio romance actions are more successful, or Leo's gain more confidence from compliments, that sort of thing! There's many different ways they could be brought back!
More after school clubs for children that boost skill gain or grant reward traits
More hairstyles for toddlers
Any new careers added with EPs/Game packs have a relevant degree (doesn't have to be new degree's added, that would be awesome though)
Would love to see more crafts and hobbies added eventually, like pottery, jewellery making etc. that can be sold on plopsy.
Careers - sims 3 I'm looking at you! Would love to see more active careers, such as tattoo artist, firefighter, private investigator, and stylist brought back. They were really fun to play. Hairdresser, magician, tarot reader and estate agent would be fun too, active or not!
Think thats it for now haha