The concept is basically a realistic gritty medieval warrior with fur pauldrons and a painted on skull symbol. How close are you sticking to the concept, or how much are you going for the medieval Frank Castle look versus some guy turned punisher look? The main defining feature is the skull symbol because it's not much…
why not get a real fake skull? That would probably help a lot more. You can get super cheap accurate skulls on ebay. This guy sells legit anatomy stuff, I've gotten a skull from him before. http://search.ebay.com/_W0QQsassZbiovere
i overlayed a human skull on your side view. given she is still at a developing age and her skull is still growing, its not accurate proportionally, but it will be close enough to give you an idea on where your off, and how to construct your skull a bit better.
I think I see what threw you off for the skull. Skull 5 is a drawing, and it looks like they made a few mistakes on it. I would recommend trying to find multiple views of the same skull. That way you get consistency across all views
This is hopefully what it will look like, on the top view it wont show much of the skull but just the hair, while the window will show the full skull more