Any ideas on builds would be helpful

, so healing is what you'll have to do.
Smite hex works wonderfully too. I like the knock-down signet as well, followed by a skill which I don't remember now (my bad) but that deals extra damage when the foe is on the ground. Sorry if i cannot be more precise but i've played smiter only 2-3 times ever.
(not least because the undead axe thingies take over 300 damage per hit from signet of judgement if they use frenzy
)
Smiting Prayers against a Necro with Armor of 70 will feel pain. Extra 5 points from holy damage will hurt if you continually launch smiting attacks on them. Judge's Insight 20% armor penetration, holy damage, extra 5 points of damage from holy damage, it all adds up.