I like the composition and the clouds. They are so fluffy. :3
For some reason, the black sky is terribly pixelated. If I were you, I wouldn't go for such a dark color, but I'd choose a dark shade of blue and I'd tone everything in blue to indicate it's night. The characters on the right are too bright and colorful for a night scene.
The moon could be edited more - it lacks some outer glow plus it looks too 3D compared to the rest of the image.
I don't think you're that rusty, tho; the wall just need some more editing to get closer to today's standards but the initial idea and composition aren't "half bad". ;)
