What if we had Inquisition as a passive pally/holy power buff?
With every charge of Holy Power accumulated, the paladin deals an additional 5% Holy Damage.
With that setup, tons of things could be bounced off this idea!
To keep ret as the 'primary' damage dealer, it would be a simple matter to perhaps have something as:
-Physical damage is increased by 5% per Holy Power. [Thus, 5% phys/holy damage bonuses per holy power. Sounds nice)
-While maintaining 3 Holy Power, you deal 15% more holy damage. [causing the holy power scaling to be 5% -> 10% -> 30%]
Or how about something more basic...
-Healing done is increased by 3% per holy power maintained.
-Critical Hit chance with all spells and abilities increased by 2% per holy power maintained.
-Increases chance to dodge and block attacks by 2% per holy power maintained.
Just thoughts swimming in my head, figured I'd put them here before bed.
EDIT: The reason why I also thought of these, is in part due to a blizzard post I once read, saying that these aren't quite like combo points in that they should be -immediately- spent. With a slight buff like this, I can see paladins holding onto their holy power for a short while before spending it (Some cases excluded of course). Perhaps it wouldn't help at all, and spending holy power right away once the magic number 3 is hit. At the very least, the constant ramping-up might be interesting!