Use the improved devotion aura points somewhere else if you have shamans in your team. Their totems will give you the same extra armor and you can use retribution aura with no problems.
Also with the crazy armor values on items in TBC and WOLK you will not need to use that aura. I have invested these 3 points in the improved hammer of justice. It makes my paladin a bit more useful in BGs where some suicide charges to my group just to get stunned by the pala


Other than that, the build is good