This piece looks really great, I love the sense of spiraling movement. As far as those yellow flowers in the bottom foreground, perhaps adding a little bit of that darker orange at the top of the painting to their low-lights would help them pop out a little more. That would also serve to help the viewer's eyes travel from the foreground, to the hair, then back to the background, where, hopefully, the cycle starts again. I think it would add a less subtle spiral that would really make this piece even more cool than it already is. And also, maybe it was just your model, I don't know, but the horse's ear closest to the viewer seems a bit off. The white curve seems like it comes in too soon on that dark interior of the ear, maybe its just me though. I would have posted this in the critique section but I guess we both have to have premium for that to work, so I'll post it in the comments section haha.
When i saw the in progress i was wondering how much detail you were going to put into the flowers and if it would distract from the girl and the horse, i'm glad you decided to leave them subtle. Very nice painting, really stunning