watch your headroom in a couple of the shots. like the first for
example. it'd look a lot bigger if there wasn't as much sky above
him. and it's just dead space that takes away from the focus of the
photo. also, it'd be cool to see more of where he was coming from and
where he was landing. give it more of an idea of what's going on in
in the second shot, it's a cool idea to try and incorporate the camera in there, but the lcd being in front of the rail and landing definitely takes away from the shot. i also think you could find a better angle for that rail. it took me a little to understand that it kinked to the side. try shooting it horizontal if you want to keep the camera in the foreground. it'll give you more room to fit the camera into the shot. and it'll cut down on the dead space that you have above the rider.
for the third shot, i think i've got a great angle for the jump, and the foreground twigs work well since the colors match so well (they'd work better if they weren't covering the rider partially). but the lurkers draw all the focus in this shot. if the rider was framed above the lurkers (between the twigs without them underneath) it'd be a better composition (less centered) and you wouldn't have to wonder if it was a picture of someone hitting a jump or of some kids standing on the deck.
on the last one, it's good because you can see his face, or at least the front of him, which is normally hard to do with that trick. only problem is it doesn't give a good view of how he got up on the rock or where he's going after the stall. shot could still work like this, but you might want to put him more in the rule of thirds areas or at least a little looser to give more of a feeling of what's going on. he's a little centered vertically right now.
lastly, how are you compressing these and what adjustments are you doing in photoshop? the third one has a good amount of saturation, but the colors are pretty dull in the rest of them. unless you're going for the desaturated look.