There were a few laggy parts. One problem was with movement. It seemed like most of the time I couldn't move in more than one direction at a time. Also, the boss' body parts just kinda flew around at random at the end of each battle. Not sure if that was intentional. It was actually kinda funny and made for shooting the parts for extra money fun.
The overall gameplay was a little easy. That isn't a bad thing, because it allows for me to enjoy all the nice weirdness you have going on. The music fit in well, and the concept is attractive and unique. Even without medals I went through and played the Hard Mode option after I was done with Normal. The leveling system is fair and well-balanced, even for an easy game. I like that a lot. The dialogue was humorous, adding to the overall enjoyment. The fast pace of the levels make the dialogue seem less repetitive in the end, as well, which is very good. It never got annoying.
The only bad thing I can say is the lagging on the movement. That really wasn't even bad enough that it was insufferable, and did not deter me from wanting to finish the game. The only things I could suggest are more music variety, and possibly the addition of medals, but those aren't necessary for it to remain a good game.
Thank you for putting so much work into this!