Interesting idea. The domes wouldn't have reflections, being behind the rocks, but the rocks would. The reflection of the creature's tail at left needs alignment, and IMO there would be some ripples around the objects in the water.

Very imaginative, but the focus clarity of the image is too inconsistent to "read" smoothly to the eye, particularly the background behind the items in and on the water. Some selective blurring will help push the background down and make your focal point of the water stand out more. I would also slightly darken the background behind the ship sails to help them "pop" a bit more.

Also, since this is a "night" scene, you need to adjust colors. As a very old song used to sing "Red is black, and yellow, white..." At night, yellows are not yellow, and the green would be black...While there may be yellows, they would be from incandescent lights. Yours are giving a blue cast, making the color situation even more noticeable.

I love your concept and you turn the sourceimage in several ones. Great, GL

So much lovely work done here...too bad it will go unnoticed because of the lack of a dominant main subject.