I didn't vote on this, but since you're asking for some points, I'll give you my amateur guess as to how to make it a bit sharper/more appealing. If you shot in raw you can probably track down the focal point of this image. My guess is that it is on the horizon, which is crystal sharp. The foreground, however, leaves a bit to be desired, in both exposure and detail. It's not out of focus, per say, but the details could be more engaging.
I would have gone with a focal point on the shell or the rock, and then a small aperture to maintain focus until the horizon. It would have helped with the exposure of the foreground as well.
Since this was advanced editing, you can try to use more tools. With a shot such as this you'd need to. Either an HDR-type blend of exposures to save the detail in the sand/rocks/shells while preserving the awesome color of the sunset. But HDR isn't for everyone, and it can get cartoonish in a flash if you aren't used to it.
Or, working with the raw file to preserve as much of the histogram as possible, and then working with layers, dodging and burning, and possibly some exposure adjustments. Shooting into the sun is a tremendous challenge (there are blown out bits in the sunset while at the same time under-exposed bits in the sand/rocks; so that's the challenge right there), and you honestly need to use everything that's available if you want a shot that'll compete with, um... hummingbirds ; )
Again, just my amateur guesses here (you can see I don't know exactly what I'm doing and I'm here to learn as well), but that's at least what I would do.
Regardless, it's a lovely photo, and 135th place is nothing to sneeze at in a free study. Best of luck.