Well, I’d like adding Demons to Sanctuary if it wasn’t just adding another Zeal variant. Sanctuary has Knockback on the pulse. What if you also made it so the pulse triggered on striking?
That way it’s still useable by a Zeal Paladin to handle Physical Immunes, but the knockback effect makes it less desirable as a main aura.
However, a Charge Paladin would benefit greatly from the knockback effect on striking and it would also give him a slight area of effect damage (since the pulse also does magic damage). It’d give the Charge Paladin a natural aura to use. When confronted with non Demon/Undead the Charge Paladin could switch to Might/Vigor and have to kill them more slowly one at a time.