Thanks to all of the constructive comments on the last Sketch of the Day. I've made some major revisions and here's the result:
I wanted a barbarian type of look, of a savage who's raiding more civilized cultures around him. I definitely wanted a more thick-bodied draft horse look rather than the sleeker Arabian in the first version, which I think I got.
Ultimately I think this was an interesting experiment that's not quite working out how I wanted.