starting off the wizard...or mage seems to be the strongest...you know when you finally kill the necromancer tyrelon....if you are observent you will find other higher monsters wandering around ...now as a fighter and ranger i couldnt kill them all..but as a wizard i killed them all easily...all you need in the begining is the metorite spell.
i havent gone out of the village yet...so im not sure as to whether the orcs will be resistant or not to them...i will have to wait and see.
i think that in some cases when you buy beyond divinity you get divine divnity free.