In the video, he was feeling his oats there I think; typical reaction of the confined horse getting some air (don't need to bother with a discussion on his kicking out as that's been covered).
What I saw in his movement was restricted upward and forward motion in his front legs which, in my humble opinion (and I hope the jumping folks will weigh in here), means he's going to work that much harder getting and keeping those legs in decent position for clearing a jump.
Overall, I liked the look of him (of course I am partial to a thoroughbred) apart from his front legs. I don't think he could handle a second career as a full time hunter/jumper though so it would be kinder on him to focus on flat and trail work. Thus, if you could content yourself with minimal to no jumping on him, then it might work out for the two of you.