Here's the final (pending approval from  LaurenRivers).

I tried an experiment with hair highlights--I drew white bars along the contours of the hair that would be facing the light source, then I spread the bars using the smudge tool. I think it worked out pretty well for my first try!

This was a lot of fun to do, first because I've never done an equine before, and second Lauren's character has a lot of... well, 'character'. This portrait gave me a lot of opportunity to work with hair effects, because her hair is both long and multi-colored. If you look closely, you'll see my attempts to blacken the hair roots and blend the two colors together in a manner that hair would natrually do.

As always, constructive feedback is always appreciated.

EDIT: On suggestions from Lauren herself, I have added color to her blouse. (Reload the page if needed) She has now given final approval to the portrait. Thanks Lauren! This was a lot of fun to do.