I love how you really went in there and hit the blackest blacks in the shadows like the nostril and the inside of the back leg. I think you need just a little bit more of that in the inside of the front leg to add some more contrast. I also think the white highlights you added specifically in the tail add to the drawing in a great way, they really help with movement and shine. The only part where I get a little lost is the front hoof as the rest of the image is very stylized but that front hoof looks very defined- it could be the way it is rendering on my computer though too.
Overall I love your style, the mane and ears have so much character. I feel like you know the form of the horse well.
"Whenever you feel like criticizing any one just remember that all the people in this world haven't had the advantages that you've had.” - F. Scott Fitzgerald
I don't hear well and therefore I don't spell well... please don't pique on me!