Hey Michael,
You are certainly comfortable and solid on your board. As an instructor, the first thing I look at is your stance. Your stance is the most important thing to get right, as it has the biggest affect on your riding as a whole. If you correct your stance, you will find the performance of your riding will improve significantly. For that reason, let's concentrate on your stance first.
You are counter rotated when you are riding straight, and most noticeably during and after a toeside turn (this is common). Counter rotation means your upper body is out of alignment with your snowboard. Your upper body is sending mixed signals to your lower body, and in turn your snowboard. Have a look at the video; when you are riding straight, your back hand is trailing out in front of you (off to the toeside of the board), your upper body is open and facing down the hill. Now look at the video during and after a toeside turn; you will be able to see it more here. Your upper body completely opens up and turns in the opposite direction of your snowboard. Look at the images below to get a better idea of what counter rotation looks like.
When you ride straight or turn, your upper body and lower body should be aligned and stacked directly over your snowboard. When you are aligned over your snowboard, you are in a much more stable and responsive position. This will help steering, edging, and pressure control, which in turn will enable you to increase the performance of your riding.
As an exercise, try riding with your back hand holding the side of your jacket, just near your bottom. Keep your front shoulder pointing towards the nose of your board and the direction of travel. Try to be aware of keeping your upper body aligned with your snowboard. Keep thinking about your back hand. Keep your upper body
strong.
I'll let this idea sit with you before we move on to other ways of improving performance. When you fix your stance, your riding will improve significantly, and the performance will naturally increase. If you have any question at all, or if you want to share more footage, please don't hesitate to do so.