Hey, the bullet patterns for the bosses are so nice and varied, I think the hardest one for me was the castle, I lost 3/4 of my lives thinking I could maybe find a safe spot between the lines :)
Art style and animations are top notch.
Some of the abilities you get like the 360-spread and homing rockets make me wish there were stages with regular smaller enemies between the bosses, but boss rush is cool as well.