I 100% agree that there shouldn't be a new world with a generations pack. The budget should be used for new animations and unique objects. I also agree that we don't need more clothes for young adults. We need more focus on toddlers, children, teens, and elders (and babies if we get better ones). We need more activities for all of these life states. I want to be able to take my toddlers for a walk in a stroller, but I also want them to be able to go to their grandparent's house for a few days. It would also be really awesome if we could have sleepovers for children and teens, but I would also like a non-romantic option to invite family members to stay at your house during the holidays or whenever.
I want grandparents to tell their grandchildren stories about their own childhood/teen years. I want a bake or cook with grandma/grandpa option. Child sims should be able to dance with an older relative by standing on top of the adult's feet. It would be funny to have an interaction "In my day" where an elder sim gives the speech of "In my day we walked 15 miles to school and back..." I'm all for the return of the midlife crisis as well. Elders could also be an option for childcare instead of a nanny or preschool. My grandma watched me when I was a toddler and my parents were at work. Teens should also be able to be hired to babysit children and toddlers.
Teen and child sims should have more options for being involved in sports or other after school activities, but I don't want it all to be rabbit holes. I want to follow them to some of their gatherings or events. I want the costume trunk back, but I also kind of want to see sims be able to perform in a dance recital or a play at school. It would be cool to add arcade games and comic books, so kids and teens can go to an arcade or comic book store. They could upload these builds to the gallery for us to place in our towns. I also want mini golf, so families can go together or teens can go with their friends. Maybe we could even get a skate park? Again, these places would be lots we could choose to place. Teens also need more to do socially. I want the hangout option back where they would sit around on the floor an chat in a group. Slow dancing should be added back, and I want proms that we can actually attend. This is probably unlikely, but I wish they would redo the teens to make them actually look like teens. I wish they were a little shorter and looked a little more awkward (like Sims 2 teens).
There is a lot more I'd love to see, but I will leave it at that. It's supposed to be a life simulator, but there are huge parts of life that are still missing from the game.
