It occurred to me... Fear in the Sims isn't even a new concept. The Sims 2 for GameCube had Fears in opposition to Wants. Mostly, it was small day-to-day fears and they would change often. Fear of a fire breaking out, missing work, romantic rejection, a burglar, etc. Somehow, though, the idea was never incorporated into the emotion set for 4. I like the idea mentioned earlier of the option to give Sims one or more Phobias and even the possibility of letting them overcome certain fears (like a Sim who befriends the Grim Reaper would no longer be afraid of him, since they have a close relationship.) Certain Traits could even be applied to deal with Fear. Fearless, Courageous, Nihilistic, etc. You could use them to make adrenaline junkies, emo/goth Sims, and so on.