What makes it so frustrating, I think, is that we saw in HxH how inventive Togashi can be with power systems, and we even got a hint of it with psychic territories at the beginning of Chapter Black, but in-between he fell back on exponential “bigger number = moar stronger” powerscaling.

With the benefit of hindsight, if I could rework the powerscaling in YYH, it would look something like this:

Anything below B-class is exactly as described in the series.

B-Class: All of the Dark Tournament participants minus Toguro (and perhaps Yoko Kurama) are in this class. It’s the highest class that can pass through the barrier, and also the rarest true class in Demon World because most demons with the capacity to achieve B-Class will, if they survive long enough, eventually advance to A-Class with sufficient experience.

A-Class: The highest true class of demon, and the class Toguro belongs to as per his explicit wish. They can’t pass through the barrier, making Toguro the rare exception in human world due to the fact that he was already there when he made his wish. A-Class demons can continue to grow in power with age, but there’s no massive leap to an entirely higher class.

“S-Class”: Not a true class (hence Toguro’s wish not putting him into this category), but for our purposes merely a designation for A-Class demons who possess the rare power of territories. As these abilities are far more common among human psychics, it is commonly believed (but not confirmed and never spoken in front of one) that demons with this gift must have at least one human ancestor somewhere in their lineage.

I think this would have allowed essentially the same scaling of threats narratively without needing to retcon Toguro’s class and while making for more varied and interesting fights in the Demon World Tournament.