Segorah Bid

Sketch for my bid for a very particular Segorah horse. You should all check them out here [link] there's a store raffle involved and stuff!
Edit: I did the flats but I want to keep which one I'm going for secret >_> Instead you guys get the background thus far!
Edit: Now you might be able to start guessing who it is. I shaded this in greyscale, started doing a cell-shading style and then blurred it to get really tight, controlled shading. I've never done that before and I love how it worked out!
Edit: And now it is in full color, still in need of some tweaking and touch-ups but otherwise completed!
Edit: Tweaking and touch-ups completed but it still doesn't feel 'done'. Any suggestions?
Edit: Did some lighting tweaks... feels like 95% there but... I don't know. Seriously any thoughts? ANYONE?
Edit: I haven't been able to think of anything to change or adjust, but something's still not sitting right...