I disagree with some other people, I personally think he would be great at hunter/jumper and may also have potential in dressage. However, he looks like he has a bit of a straight shoulder, and either a sloped back or high withers. That means before he gets deep into training, and gets the correct muscle in the correct places etc etc, it will be a rough ride. Also, im not so sure about his little feet, but he is very cute!
good luck with him.
P.s. I don't know what you have done with him already (already started jumping, etc?) so im sorry if I made myself sound stupid. Lol.