+1 to the notes from Jaco. I would also suggest listing controls on the side of the screen so the player knows how to ride around. Also maybe a button to reset the character when they flip upside down, I had to restart the game whenever that happened.
You could also record a vid and show us what the game is capable of, I couldnt achieve much as my character kept on ragdolling ¯\_(ツ)_/¯
Love the vibe, butt skating is a wonderful concept and Id dig to see this with some more polish