With regards to the party priest, I'd like to recommend Dominic, a fanatical member of the Anama kicked out of Shayder for unbecoming conduct (He was a bit of an embarrassment, so they sent him off to "spread the word" in Avernum). Accusations of heresy are frequent, often concerning things that have no connection to the arcane in any way. A small pebble for example.

Advantages: Pure Spirit (At least, so he says)
Disadvantages: Sluggish (Due to having to stop every five seconds to berate a tree for being magical)

Skill points in to Intelligence, Priest spells, Thrown Weapons, Spellcraft and Luck if there are any left over