Since most everything I'd advise has already been said on the first page I'll just mention a couple little tips. Patrol mobs, being one. Pretty much everything after the HM has them. Single creatures that keep following the same route which also usually overlaps with another patrol mob. Either pull them first, ideally, or if they're far enough away from an all melee mob, grab that mob and run them back out of the patrol route. Just watch for pesky ranged creatures that may just sit there. Which brings me to ranged creatures. They can be a pain because they don't want to move and going to them often risks pulling something else. Easiest way to get them to move is to break line of sight. Pull the melee creatures in the group around a corner and the ranged attackers will come to you till they can get a clean shot off. This should allow you to then get everything in a group safely for some quick AOE burn down.