• new layer: underwear_gender (man, woman, none)
• bodies (man, woman) → human (everyone naked)

• bodies human → human_[white,black,brown,yellow, etc]
• bodies gnoll → gnoll_[brown, pink, violet, etc]

• heads head_class_subclass → head_race_skinColor (no hairs at all on heads)

• hands class_animation → race_skinColor_animation

or!

Define palette remap from current skin to all new colors.