I tried all of the traits with various playable Sims before coming to the conclusion that I have no use for Romantic, Hot-Headed, Goofball, Cheerful, Squeamish, Good, Evil, Erratic, Mean, and Family Oriented.
For NPC townies, I don't like Romantic, Lazy, Kleptomaniac, Erratic, Slob, Glutton, Mean or Evil. In my game, almost all of the adult bartenders, baristas, and restaurant staff generated have at least two of these traits.