The EP that is basically the Update we have been begging for...

Since there has been no hint of fixing/overhauling Sim traits/personalities/autonomy. Instead has been Band-Aid'ed recently with Custom Venues, and Dynasties and since EPs are the only way for it to be done fine... make an EP dedicated to: 

• Fixing/overhauling Sim traits/personalities/autonomy at the Sim level (not with Clubs, not with Custom Venues nor with Dynasties), as a free update with the EP.
• Add more traits, lifestyles, etc. cross pack expansion features. Also update Lifestyles such as Hungry for Love/Single and Lovin' It (one is too hard to get/keep and the other is too easy to get/keep).
• Actual family tree editing at the World Management/Editor level, managing and connecting, adding ancestors/descendants, and a non-breaking way to add NPCs such as Grim Reaper to family trees (for Grimborns), etc.
• World and hidden world/lot editing at the World Management/Editor level. Let us be able to edit without live mode worlds/lots/households before we even start our game. I hate how much I have to go in and out of world management, households, switch households to set up a gameplay. I want access to spawners gosh darn it!!! If you won't insects/butterflies to all worlds I will!!!
• Create-A-Style, even if you are not going to give full patterns and colour wheel at LEAST let us be able to use the same colour schemes and swatches cross packs! So many similar but not matching enough swatches that class or don't really match make using multiple packs to dress or design a lot is so frustrating. The stupid amount of non-matched medium-dark brown woods, black/dark greys, and golds alone drive me nuts (some times I have a room with like 6+ different gold accents and 3+ wood colours or blacks).
• Toggle pack features expanded (as a free update).
• Skill/career Lock feature: Lock Skill/Career Gain Progress Type Feature | EA Forums - 12598218
• Adding/fleshing out some CAS simple adding hair styles for missing age groups or genders, adding more facial features, etc.
• Fix auto generated towny outfits, a lock or block from auto generated Sims from wearing. Just let us decide what they will wear with "default" only Base Game allowed and we can allow/toggle on our own, or by Occult or By World, so world outfits make sense.
• Add skills/premium items people have been begging for. There is really too much to list but I am sure the EA team knows the top wants.
• Update/clean up the Simology tab! (as a free update). It is crazily getting out of control with the more packs you get.

I won't mind if this EP has no new world as it will give access to hidden lots/worlds, I don't mind if they skip Build/Buy items as Create-A-Style would make up for that. I would pay for this update though more than half of this should have been free/an update.

edit: 

• Ideal cross-pack cohesion. There are, at this time, so many missed opportunities for cross-pack gameplay it really sucks. Though it is noted when there are cross-pack capabilities, sometimes it seems more for unscrupulous intentions for purchasing packs (for example Legacy's Event CAS EbN Dress has some people upset). I feel the biggest forgotten cross-pack homage is for Stuff Packs and Game Packs, I can think of RoM (no copypasteo for apothecary ingredients or items) or CCSP (no new jewelry, updates to Moonstone for fairies EbN, no crowns R&L, etc.) for example.
• Skills UI and expansion, it should be updated similar to Sims 3 skills (click to open statistics and challenges), all skills only with 5 levels updated to 10 and more level features added (for all the skills/packs). Some skills with only 5 levels, could be expanded with cross-packs. Entomology for example works with OR, S and ECO to an extent but it be better if they were actually better in cross-pack capability and when up to Level 10 (especially with the other packs). I'd love it if there was a more medieval version of Archery in a future pack to merge with AA Archery and increase to a level 10 skill.