I quite like the concept and the juxtaposition. I'm not sure about the blurring of the plane/ship, it seems to distract. And the glowing crystals and some of the mushrooms seem to be a bit too large - they overwhelm the foreground and distract from some of the nicer detailing (e.g., the decaying stonework).
Thanks for the great feedback. I agree, looking back I'm not too happy with the placement or size of the blue crystals on the left. The ship does perhaps stand out too much; although I felt it necessary to add something to avoid the piece looking too sterile. Couldn't think of anything else at the time!