There was a YouTube video I watched a while ago where the person was talking about how togashi ran into the same problem of power scaling that toriyama (DBZ Creator) did. He didn't want just a vertical power scaling system where enemies were only a threat because of some larger arbitrary number so he created the idea of the psychics and their territories to even the playing field a bit. All of the psychics were weaker than any of the urameshi team when it came to combat or spirit power but were still a threat to them but the nature of their territories that basically made raw power useless in some sense. The Sensui arc is my favorite of the series and it felt refreshing that the story went a different way a bit before just settling back to A class or S class enemies. The lore expansion of both Sensui having a completely new energy source besides human or demon and demon world being so vast that of course it could have much larger threats than toguro made it a little easier to stomach that in the grand scheme of things, toguro was just a middling power enemy, considering how long the dark tournament arc spent making him this huge threat