I'd say he's on the forehand in the video you posted. To help my horse use his hindquarters more, I do lots of hill trotting, and in the arena I do lots of transitions, half-halts and circles. Another thing I do (especially at the canter) is make myself sit deeper, in that I will literally hold my butt into the saddle if I feel he is too unbalanced in order to slow him down and squeeze him through with my legs. Try working at the trot before you try to collect his canter.
Otherwise, he is a pretty boy. I like the idea of him for hunter.