I'm not a farrier so I don't know what his hoof will look like, but I think that with a lot of patience and time you will get better results than if you push him to run around. I know you can watch him every second and what he does in the pasture - who knows. Are you thinking about some corrective shoeing to help his legs and him be more comfortable, that way maybe he won't do himself any harm when he's 'jack'n' around in the pasture.
As for me I would still work with him, but it wouldn't be riding orientated. You could work on ground manners, work on some cues to lower his head, things like that so you guys get to be around eachother, bonding and all. This maybe a set back as far as you getting to ride, but it could be a huge advantage for you to get a horse who has had a lot of practice with manners and anything else you can think of.