Alien refresh—more alien-style clothing, improved powers, etc.
Aliens to be a more fleshed-out occult.
Sim government agents going after the aliens, and them trying to blend in as much as possible.
Better secret societies (want them to have more impact).
More venue types: convenience stores, malls, areas that can hold events.
Functioning cars and motorcycles.
A refreshed detective career, more cases, less repetition.
More space worlds (maybe some as vacation locations).
I know we have spellcasters, but can we add witches? They could be the villainous versions of spellcasters.
More selection of windows usable on round walls.
More stained-glass windows, not just tiny circular ones.
Sims being arrested, etc.
A child support/benefit system.
More cyberpunk items and clothing.
More prosthetics, such as legs, arms, hands, and eyes.
A wider range of eye patches.
A public transportation system.