Base game updates:
• Cars, carpools and buses
• More than 8 Sims Max per household
• The return of the Epic Lifespan from The Sims 3 (still missing, the maximum lifespan is currently Long, not Epic, that one is still absent from TS3)
• In addition to Epic Lifespan, another update addition should be Customizable Lifespans, a feature previously added to The Sims 3 in a game patch, basically we could adjust the length of life stages to our liking/preference
• Spiral stairs
• Create a World tool or Neighborhood Editing tools OR a new plain world like Newcrest but in another setting (possibly desert?)
• Color wheel for hair, eyes, Sim skin tones
• Tattoos overhaul with a color wheel and new customization tools like patterns and tattoo placement options (possibly with a GP or EP that may include Tattoo salons and a new business/career)
• Custom Styled Looks that we can save and share to Gallery
• More Gallery base game improvements and overhauls
• Preteens
• Older Adults/Middle-Aged Adult life stage
• Graveyard public lot type or lot trait
• Owning more than 1 home/house
• Owning Vacation lots (yes, I split this into two different updates, as maybe some people can have more than 1 home AND a vacation house in addition to them)
• Capp and Monty families (the Romeo and Juliet family drama should maybe come back to Sims 4 somehow)
• Landline phones
• Option to turn off phones and modern electronics for certain worlds or saves
• Newspapers
• More off the grid compatible objects
• More Infant hairstyles and clothing
• Game Time overhaul: adding more time in real life per Sim minute, so that Sims no longer have to be late and take a million minutes to walk to important meetings or appointments and like university classes, school and work, and this would overall help with managing daily schedules…hmm speaking of schedules…
• Some kind of micro-manager tool for the Calendar (since Calendar is now basegame) called Daily Routines/Weekly Schedule for Simmers who love to plan out every Sim week and weekly and daily activities for their Sim families and households.
• Genealogy/Family Trees overhaul so we can see more family relatives like cousins, uncles, aunts, nephews, nieces, second cousins etc.
• More basic common harvestables like oranges, chives, leek, spring onions and kidney beans
• More CAS columns
• Ability to remove the other Railing for the stairs so it will no longer overclip with the wall
Edit: how did I forget cars haha oh my! Well now it's on top of the list <3
Edit #2 : I added other important things like more than 8 Sims per household and custom lifespans/Epic Lifespan.