You need to list it's Hit Die.
As Bhu and Milskidasith pointed out, this class needs full BAB since it really doesn't get any good ways of increasing it's AB in any other way (spells/powers etc.)
Ditch the leadership nerf, and just say that the Wolf Warrior get a number of wolf companions in addition to the normal followers. Winter Wolves are only CR5 anyway, and they are the toughest ones on the list. Basically a toned down animal companion.
Givet it more skill points, 2 is way too low for anyone, and this PrC doesn't base anything on INT, so there will be no great boost there.
Power up the shapechange ability, as it stands right now it's extremely weak and you'd probably perform better in almost any situation in your normal form. Not what you're aiming for I guess.
So, yea. I like the idea, but as it stands right now it's down there with the fighter.