Fixing Ghosts?

Not being able to create ghosts in CAS has been bugging me a lot, i want that. And i miss Sims 2 where a ghost would scary our sim and they would die of fright if they see a ghost. Actually, all of your ideas are really cool and i hope they add that to the game.
Maybe they could add some gameplay for us if we wanted to keep playing our sims even after they are dead, like a Netherworld or something!