I have a donor Enc that was fun in the low levels when you could charm and mez, but now I only drag it around to buff and help with big boss debuffs.
The new double proc buff is ok, but as it is a random chance if it procs I tend not to bother. I only keep the enchanter as it has a Donor weapon, and I dislike the fact I hardly use it.
Enchanters are going to be hard to balance I think. DPS is fairly awful with my enchanter using clicky DPS for the whole, debuffs are good on only the biggest mobs with lots of hp, and donor charm tends to be only the weakest trash mobs that a T8 mage pet could kill.
I'd like to see the rune line of spells upgraded a bit more. When I am struggling to keep heals, I just chain cast the 15k rune to help my clerics healing. Thats about as much use as I could get from my enchanter during a fight

Maybe some kind of bigger rune proc like the warrior donor 1.0, make it single target, 5k rune proc or something at least slightly useful. Similar to the caster double proc buff, but for melee. Might make an enchanter useful for the main tank on tougher mobs without breaking/overpowering, or even a lower mana 15k single target rune. Its annoying to spend so much mana on a group rune, when only the tank actually needs it.
Mana regen isnt a big issue once you have the Strange Thoughts clicky from T7.
Poor enchanters, they are fairly junk
