This horse was pictured earlier with a little boy riding him, right? (I've forgotten who posted that thread, but it must have been you, cuz I recognize the horse!!) I was going to comment then on what a nice fellow that horse was, but I wasn't on here long enough to post anything, & then I didn't get back to it.
This gelding won't win any big halter championships, but there's nothing in his conformation to ruin his use as a good family pleasure driving horse. His croup is his worst feature, it is short & kind of dropped off, but that doesn't mean that he won't be able to trot on out in harness. I've got a gelding that is built very much like yours, and he's a super little going-down-the-road horse.
edited to add: One thing I would suggest is having his front feet checked. In these pix it looks like his heels are too high, and he'll move much nicer if his feet are trimmed to the correct angle.