i agree with what was already mentioned. and for me, composition, lighting and timing are the most important things for action sports. i feel like number 1 has a distracting composition with the lift in the background and taking up about the same amount of space as the skier on the wall, and number 5 should have been shot from the other side and a second later after he was locked onto the rail. same with the grabs and for me the jump shots seemed kinda bland because of the angle they were shot from. and like was already mentioned, work on getting them at their "peak" moment of style.
also maybe a little color correction in photoshop or some of the free programs, just to touch it up and balance the colors a little more
just keep practicing and shoot everything and all kinds of different angles and you will start to get a better idea for any situation
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