I'll copy paste some objects/gameplay from previous games that I want but in a more improved version while thinking about what can realistically be included in the S4 since some of them needed a complete overhaul and I know it's impossible. Also, I do not have all packs so please correct me if there are things on my list already in the game. Here's my list:
- Wild animals and others introduced in S3 (snakes, turtles, ladybug etc).
- Optional cribs for toddlers.
- More traits like the faithful and others which were in S3 base game.
- Cleaning skill.
- Hobbies.
- Owning and managing a book store.
- More active careers or even normal careers (teacher, military, photographer, dancer, firefighter, hairdresser, stylist, cinema, firefighters, singer etc.).
- I want to be able to go to the hospital and police station even when I don't work there like the vet clinic. Female sims can optionally go there to give birth and sims can file a complaint for whatever reason (noisy neighbors, option to find a runaway pet/child hence why I want burglars and policemen back).
- The play interaction especially between children (hide-and-seek, tag etc.).
- Many playground activities (swings, hopscotch, other jungle gym etc.).
- Teaching toddlers to walk.
- I love vampires and I hope to see other life states being as in-depth as they were ( e.g. witches and werewolves), maybe in future GPs?
- If you are working on Seasons then I want season exclusive activities or even season worlds. (e.g. snowboarding, skiing, beach volley ball).
- More whoohoo locations (e.g shower, elevator, pools, hot tubs).
- Slow dancing.
- More romantic interactions at the table (taste food, hold hand etc.).
- Burglars/policemen/firefighters NPCs and maybe some new ones?
- Can we discipline children/teens caught skipping schools, please? It really bothers me not to see this option.
- Optional curfews for children and teens.
- Bunk beds.
- More rebellious teens, I would like them to run away from home like pets when things get bad at home.
- More teen exclusive activities (prom, teen parties, sleepovers etc.).
- More randomness (deaths, fires).
- Romantic interactions on beds.
- Photo booth.
- Water slides and other pool activities. Also more social interaction other than splash in pools.
- Lounge chairs.
- More sport activities: volleyball, baseball, football, badminton etc.
- Bicycles.
- I like to play in rotation but I also want my worlds to age, so it's frustrating to find a sims whose boyfriend became an elder when I came back to play with this family. I can't decide who can age and I remember in S2 you could choose up to 3 sims who can age with yours. I would like something like that but I want to decide how many sims I want to age with mine.
That's mostly all I can think of right now which I think would improve The Sims 4 greatly for me.