Everything that can fit in a cubic meter is “the size of a dog” or “the size of a small dog” and I see this as an oversight. I sort of understand where this is coming from as being fairly ambiguous with sizing gives players artistic liberty but the sheer range of something being dog sized is pretty massive. Even the descriptor of “the size of a small dog” is still fairly ambiguous as are we talking basset hound or chihuahua.
I can’t say I can think of a better descriptor for sizing other than giving an approximate height, but I feel like even something as simple as saying the huge fly is roughly a cubic foot large would do wonders for mental images.
I would also like to say I know about the descriptor menu and how I can see that a huge fly is in the small size category but again it would be nice if there was an approximate height to go with this.