This one is a jewel! Wish I could handle the rocks like you do but on a dry pastel basis. I'm currently working on a pastel sci-fi/romance graphic novel (see gallery if curious) and I totally think that your structure in the back rocks big time! But don't be worried - my concepts of buildings differ (I would be stealing from you - lol). I'm so surprised to see how many people in here produce stuff that is actually BETTER than stuff from pros. I mean, your concept - if developed could - for instance - work in a video game! I would really see your "environment" be "alive" (water movement, fog movement, wildlife, ect...) and have the controls of the flying vehicle seen on the left. It could also be some sort of hovercraft zooming in! The possibilities are really there!