Horse anatomy is tough. I'm also struggling with horses these days (some western comic I'm doing for a friend) and I know how it is. I think, by far, horses are the hardest animals to draw correctly, especially when u do it from scratch, without the references.
With some images to look upon its easier, but even with them, mistakes happen. It is a process of learning though that mistakes, and its a time consuming process. You literally have to draw at least thousand horses in all kind of poses to get some 'feeling' how to draw them correct. To me, the hardest part are their legs.
Before even u try to draw horse body u must simplify it using some plain geometrical objects, then do the sketch, then again re-do the sketch.
You have skipped that part and that's why your horse has some major mistakes which u better fix now, while the whole thing is still first wip, cause later it would be very difficult.
When I'm talking about some plain geometrical objects, I can't explain it with words, so here is the image of one sketch when I tried to draw some 'magical' horses myself.
Also, notice that the wings must be much larger (almost large as a horse itself). That's just some logical thinking, since to be able to lift that much weight, I suppose they have to be large and with great surface for lift off. :]
You can use all kind of wings, by far, the best are from the pigeons and hawks, depending: are u drawing a 'good' or 'bad' horsy :P Although, I didn't tried the bat wings, they can be interesting if u ever try do draw some demonic flying horse.
I wish u all good luck with your drawing, and don't take all critic harsh, I just want to help colleague artist. Trust me when I tell u, its not easy with horses. It take some 'research' and much work.
Good luck.
