Using 100% whole wheat gives these a whole wheat flavor. Adding a little of a different kind of flour helps prevent that – my favorites are oat and brown rice flour.
If you want a more true gingerbread flavor, swap out half of the brown sugar for molasses. Decrease milk to 1 tbsp, increasing if necessary to incorporate all of the flour.
If you don't want a whole jar of gingerbread spice mix (crazy!), use 1 tsp ground ginger, 1 tsp cinnamon, ½ tsp all spice, ½ tsp nutmeg, and ⅛ tsp clove