>>2440236I think you could improve on the colors picked for shading by picking warmer or colder hues for the shadows.
A lot of the darker and lighter colors currently seem to be the same hue as what they're shaded over, which rather than giving a convincing shadow, just makes things look dirty or wet (especially on clothing). While I see changes in brightness/contrast, I don't see many changes in hue, which is especially important to portray surfaces that not only reflect light, but also absorb it (eg. skin).
Pic related, see how the artist refers to saturation and hue changes in the color picker.
