Intense, yummy colours! They really vibrate when I look at your image. Since I don't know anything about computer 3-D I can't make any suggestions, at least not coherent ones! As you say, you're still learning, and I look forward to your future posts.
mary
Good work on the foreground water, but the clouds on the second mountain also look like water to me. The violet sun is what makes this one stand out, suggests an otherworldly place. I also like what I think is a tunnel entrance at the base of the big mountain.