This was so hard, but quite fun to do. My picks are:
$5
Big new world
Arcade or other new lot type
Bands with new instruments (smaller pianos pretty please?)
Added school activities for children and teens (they really need more to do. Ballet classes?)
$3
Majors tie into existing careers across all packs
Dorms/Roommates
New rabbit hole/work from home careers (teacher, researcher, librarian, and something more practical like mechanic or plumber)
Online classes (I really want an open university/college option for working adults or parents who want to better their education from home)
New hobby/skill e.g. origami or something like that
$1
Bunk/Loft Beds
Ping Pong
Pool Table
Photo Booth
Laptops (that sims can actually close and use on their laps or anywhere else)
I also want more interesting traits e.g. socially awkward, cultured, eccentric.