For a 15-YO, with just one year of vaulting, you are doing fantastic. Clearly you are getting some quality coaching. Because I strongly believe that you are being coach well, I'm not sure why you are asking for advice here. A pit side coach, especially one whom you work with regularly, is way better than what we may be able to see and comment on from a single video.
Here's what I see - you are not swinging well post-takeoff. Specifically, the trail leg plays a key role in the success of the vault once you leave the ground. Kirk has recently posted a great thread on this very subject and it applies to your video perfectly.viewtopic.php?f=37&t=54946
I also recently commented on another vaulter's video with similar (but more severe) swing issues. You may like the videos I linked to there. viewtopic.php?f=39&t=54938