Well as I said in a past post "There will always be someone stronger than you in the world even if you never meet that person"
The WoL is strong but the WoL is only able to perform certain feats because the WoL is protected from "corrupting" influences such as the Primal mindcontrols and ability to ignore magical protections on certain "enemies" that normally could not be pierced without such Protection the WoL has with the Blessing of Light.
The Blessing of Light does not make the WoL stronger in anyway but only protects and allows the WoL to resist and ignore outside influenced controls that the Boss normally use to give them absolute victory. When the WoL battles Primals, certain powerful Enemies, and etc it is out of the WoL pure strength, skill, and talent alone.
Blessing of Light is basically a "Anti-cheating" protection for the WoL so he or she can fight that certain enemy using their natural powers without that certain "Boss" cheating their way to victory.
Zenos on the other had is probably naturally stronger than WoL and if he had a type of blessing of Light protection he probably would be able to do the same thing as WoL, if not better, due to his strength.
The WoL view of the world has always been limited to Eorzea thus the WoL has never known anyone that may be stronger than him or her from outside of Eorzea.