This system can only be applied to 2D square games.
You are quite correct, this formula applies only to 2D-square boards. I have tried to generalize it here
I would argue that an 8x8 in 2D is also a small board, ...
A result of this suggested classifcation is an assignment of an objective size-category or size-index number. The descriptions, on the other hand are subjective. Thus an 8x8-2d-squared-cell board is classified as a category-3 sized board - whether you want to describe category-3 boards as small, standard, or maybe even glè mhòr1 is entirely a matter of persional preference.
You are quite correct, this formula applies only to 2D-square boards. I have tried to generalize it here
A result of this suggested classifcation is an assignment of an objective size-category or size-index number. The descriptions, on the other hand are subjective. Thus an 8x8-2d-squared-cell board is classified as a category-3 sized board - whether you want to describe category-3 boards as small, standard, or maybe even glè mhòr1 is entirely a matter of persional preference.
1. very big