In an intermediate revision, not shown, I added detail to the foreground and background. In this revision, I softened some of those details and improved others, including adding a ridge to the sandy bottom. I also removed a cave I had added to the mid-ground hill, because it looked like a tent and gave the whole composition a "Mars Landing" vibe rather than the undersea landscape I was working for. If I were real ambitious, I would add some fish or crabs or something. I am also still torn about adding color. Coral is often so brightly colored. A bright yellow would be so interesting here, but I'm still not sure. Perhaps later.