I'd be careful with all that stuff in the pasture (is that where you keep him or where you picked him up) I know my filly is accident prone, she somehow rammed herself into her cast iron feed tub, broke it in half and managed to get only about in inch or so deep cut down her chest, it was about 3-4 inches long though and needed stitches, it did heal nicely though. But what I'm getting at, is horses tend to hurt themselves on things they use every day, much less stuff their not used to/shouldn't be around. I would hate for something horrible to happen too!
I know of a horse who ended up getting a huge splinter from breaking his wooden fence (apparently it was under quite a bit of surface area, and the splinter was more than inch thick of wood.)
I'm sure you've heard countless other stories, I don't want to offend you, but having that boat there looks like an accident waiting to happen, and I would really hate for something to happen.
As far as the horse, he is a looker and very cute! Can't wait to see him shedded out, he's a beautiful mover. He does look part Arab or Morgan, I have two morgans myself.. and my purebred gelding gets mistaken for arabs and morabs at schooling shows quite a bit. He has a bit of an Arab head/neck though, and small enough to be an Arab. (Some Arabs don't even mature to 14h, but they are generally between 14-15h)
Too bad he wasn't papered, so you could find out for sure!