Just some comments, didnt read the entire thread so if this was already mentioned i apologize.

On your video;

- The snowboarders legs dont take any shock when he lands, he remains rigid even after dropping 20 feet, you should put a land animation.

- The snowboarding / in air needs to be differant so that the player can really tell he is in the air, try something as simple as the rider putting his ands up in the air "balancing", this is usefull so the rider can tell he is in the air.

Good job though!