The Emotions system would be considerably strengthened if Sims' emotions had a lot more impact on each other. Right now, Emotions are mostly contained within one Sim, having little effect on the other...
I love this idea here are some more: courageous, persistent, sensitive, serious, sympathetic, aloof, guarded, fearful, apathetic, stubborn, resentful, controlling, cruel, naïve, pessimistic, unfeeling, and abusive