I have to agree with the curly assessment. Definitely don't see any Arabian or Welsh in there. I know an Arabian Curly cross, and he looks nothing like that. Definitely could also be a draft cross of some sort. He's cute whatever he is!
Looks like a QH cross of some sort. Maybe some sort of pony, no arab there, but welsh maybe. Welsh crosses are very common in my area and although the bodies vary I've never seen one with that head. I see the draft too, maybe belgian cross? Also, an original thought, he might be part Connemara. They're more common than Curlies but another less refined pony breed.
14.1 is a perfectly normal size for a QH, so no need for there to be pony in there. I think he looks more QH than anything else. He's stocky more like a draft than a QH, but maybe he's had too much to eat and not enough work. I don't see Welsh or Arab, both are more refined looking. I see a white patch over his tail, and possible roaning or spotting over the rump? Is that an illusion? Maybe there is a colored breed in his background.