The way I have it figured, form reads first from contour and value. The whole thing about hue in terms of warm/cold seems to make sense also.
I'm not sure about saturation at all though, is there any rhyme or reason as to how you can go about picking good saturation? I've seen it go all over the place in the tone progression of a lot of video game sprites. Like it will max out in the highlight, dry up and pickup towards the core then dip off again. Then in the same game on another character it might have a completely different saturation progression. They'll both look fine to me but I have no idea what principles they're using to decide.