My dream pack would be a Generation and Also an Education pack that includes all ages Baby, Toddler, Child, Preteen, Teen, YA, A, Middle Aged and Elder.
Baby- I would be like the sims 2 & 3 they won't be stuck in the crib. We get to take them out, feed them like in Sims 2 or breast feed. Change them with a changing table, bathe them in sink or with baby tub, give them onesies and a beanie. Put them in a baby swing, Rock them to sleep and stroll around the neighborhood in the stroller also ride around in the car until they fall asleep.
Toddlers- I would be different I like them now in Sims 4 then I did in Sims 2 and 3. In my opinion they were absolute nightmare in Sims 2 I would skip that age so quick except for learning nursery rhymes I would like that back as a skill from Sims 2. So I would like them how they are now in the sims 4 but with Sims 3 gameplay with strollers and add daycares.
Child- I would want education pack and go to school (It would be a rabbit hole.) Like in Sims 3 have field trips but also have Sims 2 gameplay like playing hand games like Ms. Mary Mack, Playing Tag, and Play make believe around the house I also miss how the kids used to play in the tubs acting like a pirate or something in the sims 2 and also still with void critters.
Preteen- I would like this New age group to be added in game because they are not much of a child anymore but they aren't quite a teen yet neither it's the transition from a child to teen so Preteen. They are more aware of their appearance at this age then they were as a child. They'll get attracted to what they are attracted to. At this age they will become a little more rebellious because puberty they will be more mischievous and misbehave which also means from time to time attitude, door slams, and stomping up the stairs. Just imagine the sims teen moods now but more heighted a little bit. They will be more into hanging out with friends than being with family. They will still play void critters and even have a card collection they will tend to "borrow" their elder brother or sister (if you have a teen in the house.) Or most likely a parents things sometimes without asking.
Teen- I would want them to have fun like in Sims 3 having prom, but also have cliques and drama also I do like in Sims 3 where they had crushes and later on they asked them out. Let's just say I like them how they are now but with a little more Sims 3 gameplay. Also I want a teen hangout not just trait but an actual hangout spot. Also in Sims 2 to sneak out because I miss it.
YA- Same as Sims 4.
A- Same as Sims 4.
Middle Aged- Can't have kids, Actually enjoy retirement if you want them to retire early. Have a midlife crises, Take care of Elder Sims if they have any. Go on vacation more often just live life free enjoy before becoming an elder.
Elder Rocking Chair, Having a Cane or Walker, Retirement Homes if you want them to also tell stories to grand kids, have discount for being an elder.
Parties- Baby Shower, Wedding with actual celebrating, Bachelor/Bachelorette party like in Sims 3, Anniversary party like in Sims 2, Family Reunion, Graduation Party, Retirement Party,
Funeral- I would like to have a funeral say are last goodbye if we want to.