For tanks: Auto select mob with lowest enmity on cycling

[Rawrz]

Change your targeting filter to exclude unengaged enemies, only engaged/aggroing.

As for easier enmity monitoring, just look at your enemy list, orange circle =aggro, triangle=losing aggro, yellow (I think) no aggro. In a two tank scenario typically only 1 tank is managing adds, t10,12 excluded

Red is highest aggro.Yellow means closeish to gaining aggro, orangeish is about to lose aggro. Green is low aggro. Nothing is no enmity on anything.

[MeanderCat]

Red is highest aggro.Yellow means closeish to gaining aggro, orangeish is about to lose aggro. Green is low aggro. Nothing is no enmity on anything.

Orange is about to take full aggro or starting to lose it if you were at full aggro (red) from the tank's perspective. Yellow means you've just started to gain aggro or about to completely lose it from the tank's perspective.

I agree that targeting from the tank's perspective leaves a bit to be desired, especially in large pulls.

[Rongway]

Orange is about to take full aggro or starting to lose it if you were at full aggro (red) from the tank's perspective.

As has been stated previously, there is no warning that you're about to lose it. Anything that isn't red is already lost. There is a slight delay in when the mob actually hits someone else, such that if the indicator turns orange in the middle of an enemy's action, you have until the end of that action to fix the situation, but you've already lost the mob's attention, and for most practical purposes, this means at this point someone else will take at least one hit before you remedy things.