Feel of the visuals here really matches the dark but whimsical tone of the music.
I don't have any practical advice for how to improve this, I'd say that 3 out of 4 big moments in this land really effectively, some of it doesn't quite but, above all, this looks clean and technically proficient in a way that I really appreciate.
The mid-portion of this is really interesting in ways I wasn't expecting, just in terms of how you break out of editing the traditional individual battle scene and utilize clips from a couple of different scenes that don't immediately seem to go together (yes, I know they're from the same episode) and create some interesting visual juxtapositions.
Continuation of the frantic editing through the very quiet conclusion of the song (as if nothing is truly changing here or needs to change) doesn't quite work for me but that's just my opinion.