I would make male Northerners' favored class Barbarian, and female Northerners' favored class Ice Witch (Wizard, Mage, whatever).
I am impressed with the work you've done harmyn.
I have been working on a conversion of Lankhmar myself. Here are some of my ideas:
Black Wizard: As standard PHB Wizard but:
-Alignment: Any non-good
-At 5th level and every level above, a Black Wizard must make a Fortitude save (DC = 10 + current Black Wizard level) or gain one point of...