I'm a little late,But congrats on the Mustang. I work with BLM mustangs a little(broke & rode one today.)To me they are a great horse,But you must understand they are a wild animal,not the pasture pets that has been around people,auto's, family pets all their lifes.So respect that.
A young Mustang will some times bond with one person a lot like a German shepard dog will do.
So to start do not let just one person tend to it. they seem to bond to a woman or child the most.Take your time with him & you will have many years of enjoyment with him.
Oh by the way, I didn't see any thing about him that was bad,Fine looking horse,,,,