To make this a whole wheat version: Replace 3 cups all-purpose flour with 3 cups whole wheat flour and add 2 more tablespoons of baking powder.
To make a gluten-free version you can use a 1 to 1 gluten-free flour in place of regular flour.
Homemade Bisquick https://www.simplyfrugal.ca/march-mixes-homemade-baking-mix-bisquick/