The reason I rated this 5 stars is because the gameplay itself gets a bit old pretty fast and it's pretty slow paced, the actual concept and control scheme is really impressive, and I'm surprised I got somewhat used to it as fast as I did.
If you added a lot of polish to this visually as well as better execution (faster gameplay, more things to do, upgrades, possibly things like needing to fly your ship through corridors, that sort of thing) this could easily be a full fledged game that would sell well just for the odd factor.