Enchanters I agree need to optimize ac & hp. Mages I dont think it is nearly as important. If a mage is seriously getting hit he is probably going to drop. No root, no stun, no mez, no snare means that once a mob gets on you.. its game over.

Just my humble opinion.
Jarly Neverwinter lvl 42 Human Enchantress

Jarlork Firestorm
Lvl 52 Gnome Mage
-- SoC === FV --
(59 rogue/52 cleric in a past life)