The game mechanic is indeed meant to be a little challenging, however, I do get your point, since I was originally thinking of having the abilities work upon pressing their button and not the mouse click. (which would have simplified things up a bit, I believe)
The music will appear in the game as soon as I learn how to properly create a beat that at the very least I enjoy xD
The art style (just like everything in the game) is entirely made by me and I am 120% happy that you like it! I especially love the "Ultra Form".
Thanks for the kind words and for the feedback!