This just dawned on me,and I'm not sure if you want to consider it,
or even if it truly fits with in your game design.
Recently I have been reliving some of my childhood, by downloading and
reading(devouring is a more accurate description) ebook copies of the
ER Burroughs Tarzan Novels. (My fave is still Son of Tarzan).
Anyway, the idea of the "Nobel Savage", "Feral Child" or "Beast Reared" human is a motif that
you may want to add. It could be a costly event, as it would provide pretty impressive starting
attribute bonuses (namely Strength, Perception and Agility) plus some interesting Skill off shoots,
like in Tarzan's case Speaking the Language of the Great Apes.
Again, it just kinda dawned on me that it may be something of interest to your game,
then again it may not, though the real joy is re-reading all those old novels from my youth.