It's solid. I never liked this type of games but this was alright:
-I don't see a reason not to continuously shoot - make the button stop shooting, if that's ever relevant, instead
-The dim background option seemed cool, but options are not available in game
-Would be nice to see the health of the boss
-The limited continue system doesn't make sense when you aren't paying for retries
-Would prefer to not die when touching things that aren't obviously dangerous, such as side walls and ships
-Reached the second boss only