That short back is the best thing about him. They make Arab length Western Saddles and Blankets, that don't rub and irritate the hips. He looks to have plenty of suspension and he should have a nice smooth wester jog, just going by his bloodlines, Khemo & Desperado V. I can't see enough of his legs to really say anything, so look hard at them. His neck is shapely but looks thick in the throatlatch, and if you were going to show him he'd need sweating. Head looks typey but not extreme.
I will warn you a bit on temper. I had a stallion by Sundance Kid V (a Desperado V son) who was well known to be an absolute PIG of a stallion. He was difficult to get along with and had a long list of dirty tricks in the ring that frequently got him out of work until he came to me. He turned his butt to me in the stall and gave me the nastiest look I've ever seen on a horse. I walked out and said, "Geld him." and walked away. We did (he was 11) and he turned into the sweetest horse alive. He still had all his dirty tricks to work through but as a gelding, we did and he got over himself pretty quickly.
You don't say how tall he is, but my Moonie was around 15.3 and regular western saddles fit him fine.