Dire Bats would be around 471% after the buff.
Vampire Bats would be at 385% weapon damage after the buff (like base).
Hungry Bats would deal 748% weapon damage after the buff.
Note that in case of Dire Bats, they would have to adjust the mana cost as this is the only rune that´s not really channeling anything, It´s currently just floor (60/aps) * 228% weapon damage per big bad traveling bat. I´d say they have to find some sort of balance. 66 would be too low for the damage output, if I compared Dire Bats to let´s say Zombie Bears, around 95-120 mana would be appropriate.
Yeah. Direbats probably won't be as high as 471% as it is a very spammable piercing AoE. No other class has this high spammable range aoe attack. Maybe 250%ish or something but again, Plague Bat will still be useful in a lot of situations because Direbats can't pierce Wall.
Hungry Bats definitely need to be high as it's only ST attack. It needs to look at Rapid Fire's damage output for sure.