I can says this I like the game and the ay you are going with it I would like to see a variety of enemies instead of just the same ones in different colors it would make it that much better. I love the different types of guns and all but they are ridiculously powerful as soon as you have the money to upgrade them so I would make the money a bit harder to get cause as it is it makes the game to easy other then that I agree with the other comment on different bosses with a better variety of moves.
The only problem I have with it is that I forget that I have to click the bar to move it down and I use my mouse wheel to do that which cause me to move the page down I would like to see it able to just use the mouse wheel when in the achievements or characters to move it down as it would make it a lot easier