Salutations!
I see repeated instances of perfect 45 degree lines, making it look less natural. Not necessarily a negative, mind.
I suggest AA to smooth some single-pixel-width parts:
-the swimsuit bottom,
-hair on the left
-board rope
Distant stuff on the beach, except for the trees and parasol, looks mysterious. Two coconuts and an old man sitting in a floaty-ring wearing sunglasses? That's how my brain filled in the gap. Those 4 dark pixels appear noisy.
I was going to suggest more contrast on the cloud, to bring out that cool curly detail. But on my other monitor it's perfectly visible already. Dunno which monitor is displaying my colours 'correct'...
Cause the pirate ship is so close to the horizon, you might want to make it look faded out, due to that air/mist effect. Would also mean you could just have a silhouette there. The details are tough to make out as it is (low contrast).
