Wow, I wish I had stumbled into this sooner. Set, that is brilliant. I think I'll steal it for my homebrew! :)
Anyway, to contribute something, I like the ideas of orcs having connections to both wolves and boars, and here's anotehr one: bears. Strong, ferocious, enduring; they'll eat almost anything and are survivors. Works well with the cannibalism.
And, speaking of my homebrew: my setting features a history centered around a massive demonic invasion. In this time, orcs (and goblinoids) were lesser fiends bound into the service of more powerful beings. They were dredged from the Lower Planes and robbed of their immortality and powers as a form of compulsion to serve ("You fight well, we win, and you are reinstated- now get to it!"). However, the demons lost and left the orcs behind in the Material Plane as a new mortal race. Now, after three thousand years, they are more or less indigenous.