Okay I watched the video again and I think you need to take the jumps away and work him on the flat (not a lesson.. just, riding.) Someone brought up the fact to me that he seems stiff.. and now I see it too. You need to get him working on being giving and soft in his neck, his feet, his jaw.. his back, everything.
When you were trotting him, it was a working trot, but it wasn't put together. Probably because you had a lot of things going on and there were jumps you had to prepare for. I would slow this trot down with some good half halts and get him working on the rail and then figure eights, and 20 meter or larger circles. Get him bending.. carrot stretches when you are tacking up, little bits of ground work here and there. Lunging on a line directing his nose and pushing him away and forward. Etc.
I wouldn't even focus on his heavy on the forehand until you address the stiffness.
But slow that trot down and keep it very slow. Almost a jog. It's harder work and he'll learn how be very light with his feet instead of plowing them down.
When he's looser, and softer, then you can start directing him more on his hind. And I think you need more trot and walk work before you can get that canter down.
Hopefully I didn't seem rude or get too rambly. I would DEFINITELY find someone that knows dressage in one way or another.. it would benefit you and your horse soooo much. The reason I say dressage is because they focus entirely on the mechanics and deep seat to connect the horse. Though you could probably find a trainer in another discipline that is just as knowledgeable. I just speak from experience is all :)