I think it's really interesting that Shinobu Yagawa and Tsuneki Ikeda are so instrumental to the development of bullet hell shmups, and yet their games are, in many ways, almost completely opposite each other in what they expect from the player.
It's also really funny because Dodonpachi Daifukkatsu Black Label is an Ikeda game that Yagawa got to take a pickaxe to, which is why from a design perspective it's one of the funniest games Cave has ever made.