I think he could have a little standardbred in him but only because of his slight roman nose. He could also have thoroughbred or stockhorse in him because of his long legs, but he will even out. Something you might not know, if you constantly work him now while he is young and you keep the weight on him, it will be harder for him to lose weight and muscle when he is older. That is why a lot of the older horses can't keep the weight on, you will usually find that they have been starved previously or the were just that little bit skinnier when they were younger. I can tell he is going to be big in the chest especially. But what ever he is, as everyone has said he is gorgeous and so is the little filly, she is cute. I like your property and your scenary as well. Good luck with him with what ever you decide to do with him I think he will make a great friend.