Perhaps something like this already exists:

I'd like to see in one place, with a prominent duration remaining, the longest duration:

A. complete incapacitation (can neither act nor move, i.e. fear/stun/sheep/sleep/scatter/deathcoil/gouge)

B. root (can't move)

C. snare (can only move slowly) - not as important

D. silence or disarm, class dependent (school lockout is generally pretty obvious)

In addition, I wouldn't mind something like edge-of-screen glow (not full screen flashing) when either a root or incapacitate is active. Bonus points if the width of the glow diminishes to 0 just as the effect fades.

This is mainly so I don't freak out waving my mouselook and spamming shots when I could be calmly assessing and planning during the 2-10 seconds of uselessness. What I already do is scan my debuff bars and watch the time remaining. It's just not fun doing that scan.

Avion - http://www.wowace.com/wiki/Avion

It's a remake of an old mod called power auras, essentially it just has a various series of graphical effects it can do on certain events, as well as particular icons, notably, "SNARE" "STUN" "ROOT" "SILENCE" etc.

You can then specify these icons/effects to trigger on recieving certain debuffs

Thanks. Even if there's nothing in Avion for fading an effect based on duration remaining, if I can get an effect to show for the duration, what I want is just a few minutes of configuration away.

Maybe not entirely what you're looking for but it does clearly show when you've lost control of your character. Probably easy to modify to do what you want:

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