Hi
Overall the piece is wonderful!!
I just have a bit of nit-picky advice about the horse, (totaly up to you if you use it or not) the bit (the part running through the mouth), should be a metal bar, not leather, and the horse seems a little twisted in its body, you could change that by adding another back leg to the offside and place it more forward!
It may also help hid the twisted horse, if you pull the man's leg back and more under him to show the horse's elbow... but I don't know for sure that will work!
Have a great day!