Your jumping looks pretty good to me, I'd say just stay in 2point a little longer as mentioned above, and stabilize that lower leg some more. If you go back through the video, in some of the jumps that lower leg swings back and forth through the jump. Work on having that really solid and in one solid position.
As far as the flat goes, your canter looks like you're pitching yourself forward and coming out of the saddle a little. Now being forward may be a product of you being a jumper so maybe that's not so much the issue, but your butt your hips should be moving with the horse, keeping your upper body still and your butt from coming up and hitting back down. I think you're just at an odd in-between right now, and need to either commit to 2 point/halfseat, or sit back deep in the saddle. Overall, very nice work!
A horse is the projection of peoples' views about themselves--strong, powerful, beautiful--and it has the capability of giving us escape from our mundane existance.