This could really do with a tutorial, I didn't even know there was a deflect or dash until second boss. I only beat the first boss because that one time he didn't use the spinning stick attack which I still don't have a clue how to avoid.
However, some of the attack feel cheap such as the first boss throwing balls straight in your face with little to no warning.
Overall its a good start, maybe with a little more time in the oven it could shine.