I would disagree with some of the comments made, for instance, Donutz, I dont agree that ruddering is caused by weight being aft. I have actually seen many occasions when people have their weight center and fore and still use the mass from thier upper body as a counter weight to push out their back foot. I will agree that the OP is using his back foot to make toe turns though.
I also dont buy that he should be working on inclination, he already does a shit ton of that on his toe side. It is correct that there is not much edge angle, but the way he is riding he doesn't need any, he is using the small radius skidded turns to control his speed, and doing a pretty good job of it. Also, what is the goal of the hockey stop drill? I can flex my ankles knees and hips fully and get no more edge or lose no more speed. FYI sponsor turns allow your base to be seen from up the hill, not the side.
Prescription for change:
First off I would work on that toeside posture, you are a little crooked meaning your hips are still a little over the center of the board, meaning less control especially on steeps. There could be a few causes, stiff boots, too much pushing down on your toes, or just not squeezing your butt cheeks together enough. You should be looking at a straight line from knees through hips to shoulders, and your back should be vertical, not slightly inclined like it is now. (watch yourself bending over in the video)
Second I would work on some front knee steering on your toes to stop the ruddering. Get yourself to some easy green terrain, point the board down the hill flat based and get it to turn onto your toes by flexing only your front knee, no use of the arms or shoulders, in fact if you hold them out over the tip and tail of your board you will know if your doing it right because they wont move from that position during the turn. If your front hand moves over your heel edge, you ruddered.
Third, there is no flexion and extension in your riding, Im too tired to write any more, but take a lesson and work on some cross over turns, standing tall for edge change, lowering during the control and finish phases of the turns.
As always, working with an instructor who can give you feedback after every run will always be more beneficial than an internet post.
Hope this helps, happy shredding.