>> Proper power-leveling will net you a ton of piety, so drinking potions wont be a problem.
Can you elaborate? What is power-leveling?
Using potions is a flat -10 piety, pretty steep, if you drink them all in the final boss battle. And a gnome/halfling has a ton of potions at the end. Also, if you prep JJ, then you have one less slot to work with, and beads become even more annoying.