The first thing I noticed and only thing that bothered me about the shot is that the horizon is sloping down to the left ... only about 1.5 degrees though perhaps 1.4 would be better if your editor can do such precise things like my Paint Shop Pro.
Having corrected that I wonder if a crop off both sides would help ... often bigger is better and I suspect people stick with recognized formats instead of cropping for the subject matter ... it is often the subject of threads on the web as people try to fit images to paper sizes and do not realise that just because the paper is made a certain way doesn't mean we have to follow suit.
Here you have both figures on the thirds, left and right and with the horse looking left I left a little bit more space behind the man than the horse. The bits of tree/bush add to the outback feeling and without them it could be anywhere. My tuppence worth
Altogether a good shot to start posting with, nicely seen and captured.
EDIT yes 1.4 right rotation does it
