The downed lifesteal is a rather strong ability, but it isn't really any stronger than the attacks Necro has on their legs.
Hm, I know of Dragonhunter's two abilities that are meant to track(Spear of Justice, True Shot), but those are projectiles, so, it's understandable that they can miss. I remember fighting Warriors and I think it was Shield bash that was a 50/50 on me, sometimes hit, sometimes didn't.
Sword of Justice MIGHT be able to hit through a door if it's right next to it and you are standing right at the door on the other side. I know shield 4 hits through the wall as well.
I know a couple of attacks can hit through the walls and doors, including Ranger/DH traps.