I see both breeds quite well on him; my first thought though is that he REALLY needs to lose some of that weight!!! Hard to tell just how lovely he is with so much excess chub...plus that is really really hard on those legs of his...compare his body to his legs...BIG difference, and you could be in big trouble should he founder, or start developing navicular, arthritis, or any other ailments that can be brought on due to all that extra weight he wasn't designed or built to carry.
Over all, I see a decently built horse (albeit very very fluffy), he has the nice araby head, and neck, higher tail set, and nice compactish build (traits from both breeds). He has a soft eye, and appears to move nicely. I would love to see him with about 2-300 lbs less. He would be stunning, I think.
"The ideal horseman has the courage of a lion, the patience of a saint, and the hands of a woman..."