It kind of depends on your playstyle, too. Some players like to spam heal on everyone and keep the party topped off constantly. MP usage aside, overhealing can create enmity out the ass if you're too aggressive with healing and/or you have TOO MUCH Mind, giving too much with the bursts. With lots of Mind, you have to wait for your target to dwindle down a little, then time it to not generate too much threat (while watching the rest of the party).
Spamming Cure 1 without generating too much enmity can be comforting for the party, and you may even have enough MP to throw out some DoTs, too. Just as a devil's advocate, Mind is also super easy to come by in gear compared to Piety. For solo healers, running out of MP means the end of the battle, one way or another. I also don't know if Piety affects MP regeneration in or out of battle.
