Al33 nice image

"...but they are supposed to be weird, it's all fictional. "
I don't know how much you are in 3D and so...But someone who sees your image (especially the lower part )
would think of displacements made in a 3D software .
I know what you mean. But it isn't so easy to make the fictional look without "made in a 3D package" stamp over it.
The upper part is Ok (subjective) . But i would push the lower part a little more. With more detail or-and color variation or fake stones and so.
I love Space images . I am curious how far you would bring this image further.
(These thoughts above are intend to encourage you ... not to be harsh

)
Kadri.