#1 I like the colors, is the WB a bit on the cool side? I'm on my netbook (calibrated, but not sure it's right). Anyway, nice colors.
#2 I like the lonely pier shot. If there was nothing in the way to the right, I was thinking it would might look better with a bit more space showing the ocean the pier is extending into.
#3 Nice detail shot. A little boost to contrast might make it a little richer, darker darks, and some contrast to give it a little boost.
#4 Nice exposure, like the color of that guy. I would leave a bit more lead room (if possible) in front of the creature, the direction it's pointing/heading.
I Enjoyed these, thanks for posting them.