Unfortunately, I'm not sure is there's any good way to do this. But, once you hit level 30+ or so, consider helps give you a relative guage of a mobs toughness, but doesn't come close to accurately describing the mob. There are plenty of mobs that con "you could kill x with your little finger" that will come pretty close to kicking your butt.

Assuming it's simply level based, one of the simple thoughts I had was to make mobs that use weapon spec skills con tougher than same level mobs that do not.

n/t