Expansion Packs
Get to Work: Better rotational play experience when multiple Sims are in the same career
Get Together: A Club management system that can be accessed no matter who's being played
City Living: In an ideal world? Building apartments. Otherwise, customizable street festivals
Cats & Dogs: A dog-walking job, with multiple-dog-walking
Seasons: More violent weather
Get Famous: Fan clubs
Island Living: A better snorkelling/diving experience
Game Packs
Outdoor Retreat: Hiking together
Spa Day: Nail polish
Dine Out: Restaurant delivery
Vampires: A clean built-in Vamps opt-out for people who want just the build/buy and CAS
Parenthood: Allowances
Jungle Adventure: Places to live not just visit
StrangerVille: A clean built-in story opt-out
Stuff Packs
Luxury Party Stuff: An NPC party planner
Perfect Patio Stuff: More for non-adults
Cool Kitchen Stuff: More actual kitchen stuff, including another gameplay object (I'd have picked a toaster; see signature :) )
Spooky Stuff: Trick-or-treating at the neighours' houses
Movie Hangout Stuff: A cinema/theatre venue
Romantic Garden Stuff: More new romance interactions
Kids Room Stuff: Childish teens & adults able to play like children can
Backyard Stuff: Higher-quality birds and more styles of bird feeders
Vintage Glamour Stuff: More furniture in those styles
Bowling Night Stuff: A bowling league
Fitness Stuff: Jogging together
Toddler Stuff: More furniture styles
Laundry Day Stuff: A laundromat lot type
My First Pet Stuff: Letting the little critters run around on the floor