Has anyone tried high-armor gear?
[Glove Reinforcements]
[Resolute Cape] with 120 armor (or the MgT cape)
[Violet Signet of the Great Protector]
[Ring of the Stalwart Protector]
put me at 4100 AC unbuffed. I lose about 110 spell damage to do it, so I'm not really sure if it ends up being more effective, but having a Warrior white hit me for 700 (before Soul Link) is pretty hilarious.