Skaven's illo is indeed off model. Check out the Faces of Cauldron spread in issue #116 for a more accurate illustration of Skaven. And of course... it'll be fixed up right for the Hardcover release.
Actually I think he looks sneakier, more introspective and like he has something to hide in the original picture. I think the fact that he can hide behind that hair makes him harder to read.
Perhaps he's hiding the fact that he's wearing a toupee?
Whatever it is the picture in 116 works great for everyone else (love Tongue-Eater and the Cagewrights), but it makes Skaven look like a badly drawn 1960's cartoon villain or a South Park character from the neck up. I can just see him speaking in a Tray Parker voice. I mean he looks as though his head is about to explode and the pressure has nearly popped his eyes out.
I don't normally have any problem with art in Dungeon regardless of the - I hate it when it's called this but - "cartooniness". I just don't think this character was well visualized the second time around.
Like I should talk ;)
GGG