If you love a touch of the fae in your art, this gallery may be right up your alley:
Modern scholars tend to believe that the Valkyries were actually mounted on wolves, rather than flying horses. Does the second pic ring any bells? It should:
It’s based on Equestrian Portrait of Charles I, painted by van Dyck around 1637. I’m not sure how well the trappings of absolute (albeit doomed) monarchy translate to a portrait of a mounted Valkyrie, but the horse is a definite classic. Check out the shank on that bit!
Bridlepath 
beautiful paintings but that buckskins head looks so tiny compared to the rest of it’s body..
I think it was done that way so it wouldn’t detract from the king too much, actually. If the head were proportional, then the viewer’s eye would be drawn to it, rather than Charles (who wound up getting his head lopped off in 1649 anyway).
I’m pretty sure this horse looks that way because of how muscular the horse is. It’s a cornucopia of bulging muscles, and because of it it’s head and feet look small. Being an important man, he’d be sure to have a fine strong horse, and would insist on being depicted atop one.