White whole wheat flour has a milder flavor and texture compared to regular whole wheat. Feel free to swap it for any combination of regular whole wheat, whole wheat pastry flour, or all-purpose flour. I haven’t tried this loaf with any gluten-free flours but suspect a 1:1 baking mix would work well, as would oat flour or a combination of oat and almond flours. In general, quick breads like this are very forgiving in terms of the type of flour used, so feel free to experiment!