Factors that impact the "airiness" of a loaf
I'm trying to get an understanding of the factors that impact the "airiness" of a loaf (where a "dense" loaf is a loaf that's not "airy").
The recipe I use primarily is an adaptation of Reinhart's "Light Wheat" bread recipe (in "Apprentice"). I use. For the "whole wheat" flour I use White Whole Wheat (soft) which I grind with my own Nutrimill. I keep the same 5/3 ratio (by weight) but I add a few grams of gluten.
Of course, grinding my own flour with the nutrimill, I end up with a somewhat different end product so I modified the yeast (and salt) content of the recipe because it seemed that there just wasn't enough yeast to push the loaf up to double its size on the second rise. But, of course, increasing the yeast (I use instant) seems to result in a faster rise (perhaps too fast).
So -for the more experienced people here- what, in your opinion, are the factors that impact the airiness of the loaf?