Separate from that post since this one expresses my opinion more...

As a Conjurer, leaning more on survival and healing, I would personally invest points in Vitality and Piety. Vitality for slightly extra HP and defense. Piety for slight boost to MP and magic evasion. Any remnants, thrown into Mind for that healing magic potency.

As a Thaumaturge, I would probably ramp up Mind for the magic accuracy, followed by Intelligence for the attack magic. A resisted spell is a depressing loss of MP and though the stats may have small impact, I would prefer not to have a spell fail, especially when part of a combo.