any class can deal damage, depending on gear setup.
basic playstyles:
full melee (stat enough vita or get ehough life from items to sustain, get reg-gear to refill faster)
hybrid (stat enough int / vit to play safe and be able to heal yourself while not running out of mana using melee attacks)
caster ( stat enough vit to be able to withstand ep's, higher heals due to higher int)
abillity setups depend on playstyle.
mainly you should go for 1-2 which can take out a row / col of mobs when charged and 1 single target.
if going hybrid or caster, salvation is nice for high mana-efficient heals when your lifepool allows to charge it up.
i wouldnt play pure melee with salvation due to base int doesnt fit my needs. reg-gear is the key here.
play around with ability setups until you found something suiting your style of playing.