I love the main gameplay of slowly working up to a fully upgraded hexagon, and rotating around felt really nice and weighty. The art and sound are also great, but it is missing some nice particle effects.
Two things I noticed were that the bullets' positions seemed like they were still tied to the rotation of the hexagon, and that once you get a fully upgraded, fully filled in hexagon there wasn't much to do.
Other than that, the game's pretty good. Well done!