Thoughts, comments, concerns... Also what breed would you guess that he is? What do you feel he would excel in? He is 14 years old, 16 hands tall, currently getting him started under saddle. Comment away!
He has really neat coloring! From that raised tail, he's obviously a hotblood of some sort....he looks toed-out in his front feet, but I can't pinpoint any glaring faults. Very interesting coloring, with that chestnut undertone on his stomach.
I would say TB or STB. The way he throws his hocks out at the trot make me think he's a trotter but just a guess. He looks cute and you could proabably take him any way you want to. If he's sound and willing he could do hunters, dressage, jumping, eventing, etc. The only thing that jumps out at me is that he can't really get his poll high and he might have some kind of problem with his C2 or C3 joint. I would have him looked over by a vet/chiro/massage therapist. Whatever is in your area before you start asking him to do much under saddle.
My initial thought was STB. He has a very nice stride.
I don't see anything extremely faulty on him. That is a cool color, my mare looks like that in winter but then looks like a bay when she sheds out.