In epic AC is useless, casters have more likely than not quicken turnt on if they expect to be heavily hit on so don't need to succeed on their concentration checks.
That means only saves boost is useful.
Most mobs are doing damages through physical hits and when they don't you usually need to flee them (Abishai in cold form, fire breath from Velah) so you're not close to the tank or others to give them the extra saves and saving would probably not keep you alive if you don't have evasion anyway. [due to lag got hit by Velah breath once before being able to hide behind rock for over 1480hp]
That's why the aura is useful only for yourself if you are a tank with lot of HPs and evasion.
12/6/2 with 12 or 6 being paladin levels for the save aura (and incite spell) and 2 being a class with evasion usually