Nice vids! Love the tune in the second one... You looked comfortable turning, and you could tell from the video you had good speed. Only thing you'll want to work on if carving is your thing, is getting the edge up even higher to really start digging a trench. On your toe side push your knees into the slope, and on your heelside bend your knees and get your butt down!
The other thing is I know they always train people to have calm arms, but it almost looked like you had a zombie upper body lol. I'm probably dead wrong here but I like to use some arm motion as a counterweight. On my toeside I point them out towards the slope to get shift my weight further off centre (and if I hit rough terrain I can pull them back in to regain my balance), and then on my heelside I bring them in closer to my body. Kind of like thrusting movements! Ha!
Also, the buttering always looks like you favour your heel edge. You get the nose up and then the board starts turning away. One thing to work on would be to hold the nose up without turning at all (unless that's what you were trying to do).
As you can tell from my vids I fall a lot too, so not sure I'm the one to be taking advice from! But they look like fun nonetheless.