I like this, reminds me of my Cat remake I made not too long ago.
Not sure if this was what you PM'd me earlier about - but if it is? Hi!
With the way it was taken with the hair, I believe a minimalistic type of detail for the hair is needed. Mainly due to the light to dark region with the hair. As Implore mentioned, Line art with a darker blue or just black would be fine.
It's a little hard to say on what would be best since all I can see is one side of a mapped model.
(implore shhh you make better anime art than I do. a lot of people do)