Would love a medieval pack. I bought Sims Medieval and returned it because it was really disappointing in the freedom of what you could do, really constrained by quests. Something I'd want is the ability to have sword fights. Could have orders of Knights like clubs from Get Together. Sword fighting skill. Opportunity for new foods and plants. Build/Buy and CAS could have amazing options.
Could even be a medieval world and pack like a renaissance fair/cosplay thing. You could still have modern tech, but it's the players option to turn off/ignore their phones and not place modern tech in the world/builds.