Hmm you might want to adjust that crown on the forehead up or down a few values. It's hard to notice it's there. The hair would probably be brighter considering the lighting that's going on around. Considering how the neck values are, it almost seems like you might want to break up the values around the face a little bit more... Though I guess it's not really a big deal =\
Though if you're interested in giving a little bit more depth in the colors, you can probably filter in a slight amount of greens, especially in the background. Reason being is that you're using two primary hues of the RGB colorspace... Which is "blue" for the hair, "red" for the clothes. So it stands to reason you could use greens to help the subjects red and blues bleed out better.
I'll do an overpainting
Anyway, your welcome hope it helps.