If you use Divine Might, Divine Sacrifice or Exalted Smite, MAKE SURE you have replaced the buttons on your hotbar with the upgraded ones! instead of using the Tier 1 skills all the way to level 18 like I did
Actually, the same with any other "Active" Enhancement with multiple tiers like Half-Orc Power Attack, i.e. hover over your hotbar to make sure the description for the button says Divine Might IV and not still Divine Might I etc.
There was a HUGE and very noticeable difference in my damage output after making that correction!