My Eyes
Game-play felt nice, I like the way the bullets fired, and movement was alright. I liked progression from one screen to the next. The alt attacks and shield system, I had no interest in whatsoever. There were issues with slowdown/ freezing.
My main comment though: this game is incredibly painful to look at. I couldn't even play that far through the tutorial. It's not even that you need better artwork or anything, just make different choices of color and contrast. Make sure the background elements are within 10 points of each-other in value and saturation. Then make sure the foreground elements are either darker or lighter than the background elements by about 40 points. Phew