Combine sugars, flaxseeds, oil, eggs and soy milk in a large mixing bowl; beat until thoroughly mixed together. Add pumpkin, vanilla and spices, and beat another minute. In a separate bowl, whisk together flours, baking soda, baking powder and salt. Add to pumpkin mixture and beat just until blended. Stir in chocolate chips if using. Pour batter into two prepared loaf pans. Bake 50-55 minutes until toothpick comes out clean when inserted in middle of pan.