Big Bang Theory - Penny

Trying my hand at more realistic images. This is a picture of Penny from Big Bang Theory. I've put it up next to the image I drew it off of.

So far there's two key challenges. First of all, hair is rather hard to define, given that it's ultimately thousands of tiny lines. It took awhile to get it where I was satisfied.

The other tricky part is the skin, it's a lot of different colors and Flash doesn't really do shading that well, but it looks too flat with none. I found tracing the more defined lines and then painting slightly darker or slightly lighter made it look much better.

If anybody has any tips on either of these elements, I'd love to hear them.