As I was falling. The was sucked up on the bank really fast and threw me and the board down together. 

Looks ok. To improve, try more aggressive turns up and down the wave. However, at some point of life you need to be happy with what you're doing (which you probably are) and forget about stressing over more performance. 

That particular wave looks a bit fat and weak and it's difficult to extract speed and power from such a wave. You have the basics, more experience will naturally lead to better surfing.

Why is moving from moderate to high so hard 😞

One thing from OMBE I've learned is not to rush anything.....even watching the 'boring' intro videos teaches patience and attention to detail and sets the right mind-frame. Similarly, with my surfing now, i spend more time looking and feeling, instead of that mad dash down the line. cheers OMBE!