If this was ever made, it should be a simple stat, not a set of stats. I would see it counted in health points with :
1 accessible black tile : 2 x char level (x2 because we recover mana + hp)
1 health potion : 40% max health
1 mana potion : 40% max mana x char level
80 CP (counted from all inventory and accessible objects + best CP objects you could have purchased with your gold) : 40% max health (equivalent 1 potion)
Number of health + mana that one could get lower level monsters
Piety : ? No idea yet
Death protection : Maybe the hit value of the stronger monster/boss you killed
...
I know that it would be opening the can of worm, as there are so many special cases (the badge is worth more in terms of death protection, than in CP.; a class/race should calculated differently), but that could give a rough idea of left ressources.