A lot to enjoy here! Quite a complete package this is - the visuals, audio, the feel of the mech. Loved the oppressive atmosphere - makes you feel very vulnerable. Perhaps the map is a little bland, but it's enough to get the point across.
Either way, I'd enjoy seeing this expanded. Perhaps it would be cool if there was some bigger goal other than collecting rocks, something that would motivate me to play more than just a few runs.
Great job!