The graphic style is really nice, it is a very clever usage of the Voxel technique!
The gameplay is nervous and quite strategic, which is cool!
However, I found that sometimes when there are many enemies, it has readability issues. Indeed, between the differents colors, explosions, laser shoots, etc. I lose my spaceship from my view for tiny seconds, which provokes some unwanted damages on my spaceship.
Overall very nice work!