I also have 2 paragon heroes + an MM to trigger Mark of Pain. After messing with builds, I found that Malign Intervention helps tons for anyone using Assassin's Promise - you create a random minion to easily trigger it's effect. Even better, it gives you something to slap MoP on for easy aoe damage. Lastly, because it's a minion, you can put Holy Spear on one of the paragons for even more aoe damage. With good timing and micro'ing, you can x2 Holy spear a MoP'd minion for about 220 aoe dmg

It's been my fav setup recently - you get defense through the minions and paragons, while mainting strong single-target and aoe damage
