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Hey cool man! Nice sci-fi mood and i'm digging that blue emblem!
Feels like too much of a background. Think about incorporating some middle ground and foreground elements. It'll give you more depth, plus give you some objects closer to the viewer that you can get more detailed with. This will help you explore and show the over all design sense of the scene. Just mess around with shapes till you find something that fits.
Something for scale too would be nice. A building with a doorway, a vehicle or a person.
Good stuff, Rock on!
...my humble and uneducated opinion.