I just bought it and gave it a try. I have to say, it is not really my type of thing. After beating the boss, it just repeats, which is not really fun. I really liked the graphics and whatnot, but there was very little in ways of Replayability. It reminded me a lot of Xenon, but was basically over after the first boss. Still, great job! Hope it makes you rich.
Thank you for checking it out! Yes, your feedback is well-placed; it does need additional game-play elements (e.g., power-ups, shields, variation, etc.) that would give it a higher replay factor.
Again, thank you for taking the time to play and provide feedback. This was my first game, and it's clear that I have a lot to learn!