Arson should be a thing. We can do it indirectly with fireworks, but just having the ability to light fires anywhere would be fun. Could also be a Pyromaniac trait where they have to interact with fire regularly or they start them autonomously (like Klepto autonomy).
Evil and Mean sims need to do more Mean things autonomously to make others around them miserable without player intervention.
Divorce should effect children more, maybe with them taking one parent's side over the other. It would make deciding custody more interesting. Also some may be Angry, Sad or even Happy if they dislike one of their parents.
Gossip and drama should be spreadable. If your sim sees another sim cheating on their spouse, they should be able to confront the cheater or tell the spouse, both manually and autonomously etc.
