The first two bosses of variant are a delight.
Fast paced mechanics, interesting mechanics and thematic.
But the last boss is pain. It might not be later on with the strategies.

Clearing the trash isn't interesting at all. As Yoshida said, multi pull is too dangerous.

The rewards are really disappointing, the extreme feels a bit... Not extreme but far closer to savage, it's harder than P5S, P6S and P7S combined.