I think something like this would definitely be useful for the traits that are more hobby, lifestyle, or interest based like Dog Lover or Vegetarian, etc. because those kinds of traits tell you next to nothing about a Sim beyond the fact that they like dogs or don't eat meat.
Maybe there should also be a slider for Ambition so there can be a range for just how far a Sim wants to achieve a goal or how often they Wish for larger goals. I'm not sure what terms would be used, but since you have an Evil/Good slider (and we have Evil and Good traits), I figured it was worth adding even though we have an Ambitious trait.
Also, maybe Clumsy/Coordinated should have a slider. It would allow for a spectrum of athletic ability (in cooperation with Lazy/Active). For example, a Clumsy Active Sim might have a harder time with fitness over a Coordinated Active Sim. I guess I just feel that Active is itself a very broad description.
Also, perhaps an indicator of intelligence? There is already a Genius trait but maybe there's a way to put that on a spectrum.
Also Uncreative/Creative (although I guess that's sort of implied with Serious/Playful?).
Actually the more I think about it, the more I think the Traits should be only for hobby/lifestyle/interest, and then the slider should be for the rest, which would mean getting rid of the Traits such as Genius, Evil, Good, etc. And then just add more hobby/lifestyle/interest Traits to replace the ones lost to the slider.
