I like them, good use of lighting, thirds, coloring. you know the basics. The only problem I have with them as a viewer is the fact that I feel very distant towards the people in them. There's no connection for the viewer in them. On that first one, maybe have it where you are further down the rail and can see more of his face focused. Same with the second one, they just seem quite a bit distant. Maybe experiment getting closer to the riders and bringing the viewer into the picture more.
I checked out your flicker this photo is dope:
If you cropped that a bit and had less negative space up above him so the rider would be further top right I think it would be more powerful. Also, just a note. A lot of your shots have the rider facing away from the camera. Maybe try the image I posted but shoot it angled up hill. You'll get the same effect of the snow leaving the jump, and the harsh outlined light will be the same, just behind him.
Just my 2 cents.