I think that the Avenger (vengeance/conviction) type is the best to play because with concentration and blessed hammer you aren't gonna deal out enough damage to be effective, because both items and skills got better this combo might be the best for a paladin, about the damage you deal out, say you have a 100 damage sword and both skills at lvl 1.
Base dam: 100 Elemental dam: 210% This makes : 310 damage Say the monster has no resist, with conviction it is : -30 resist Total damage: 373 If a monster has al resist max it would be: 45% resist with conviction This means 215.5 dam So it would be 215.5 - 373 max damage, not bad considering 1 point in vengeance and conviction
Now taking a look at both skills lvl 20:
You should have a 140 dam sword by now Base dam: 140 Elemental dam:552% Damage with psychical resist in hell: 842 -120% from conviction means: 1854 damage if resist is max: -45 resist: 1222 damage This means 215.5 dam this means: 1222-1854 max dam with both skills at lvl 20 not counting strength and dex increase, so 2000+ damage is possible
Ok with the damage part it is ok but about crowd control, you have to wake up as little critters as possible and you don't want yourself getting surrounded so back off if needed, never run into unexplored terrain, you can also hit all the monsters once since vengeance does cold damage it will chill them and slow them down, also use narrow openings since not many monsters can hit you at once or doorways (old d1 tactic).
Another issue is mana steal, in the beginning you won't have enough mana steal to keep on using vengeance, use zeal which only costs 2 mana to regain mana or a normal attack.
I hope this guide will help you, have fun and good luck - Ramuh~(I)