[Dedzy]

The more I look at it, the more I'm with Scatter. For casters, I put their primary attribute first (Wiz/Int, Priest/Pie, Alc/Dex, Psi/Sen, Bishops/Int) and senses or speed second, usually senses. It's just sooo important to get those spells cast early on in the round, much more than the additional spell points Piety gives.
Especially with monks loaded with Senses and Speed, they are practically guaranteed first shot at casting spells for the round (not including wasps, damn those bugs are fast). This allows me to neglect speed for the rest of the group while I haste them.
I agree that Piety is nice, it's just that I think there are other things that are much nicer.