I just had to share my thoughts. I think it's very interesting hearing other people's thoughts on traits.
What I think are the most positive influencing traits:
Loves the Outdoors: Gives that moodlet from being outside
Childish: Will always get the have a blast.
All four traits that came with pets: They always get positive moodlets from being around their furry creatures.
The trait I always have to give my Sims: Insane of course! They talk to themselves, wear and do whatever they want and I love the idles! The new idles (barking, meowing, galloping) that came with pets are even better.