Reward Traits - which one is your favorite, and why?

As you note it depends on the sim what reward traits I prefer them to have, but my favourite reward trait is probably Savant since it's useful for all skill building and I like intelligent characters. I also use Observant for getting to know sims faster and Creative Visionary for my creative sims quite a lot. Carefree can be useful too if you play vampires and want to cancel out the Day Phobia weakness.