I wonder at the premise underpinning this thread because I kind of agree, Simmons' voiced Kethric Thorm didn't come across as awe-inspiringly threatening.
Perhaps he's not supposed to be that kind of guy?
I'm thinking he's like an upgraded Kagha but with less doubt and harder to make do a 180 degree heel turn.
He's commanding 'Bow', probably a 4th level slot to affect all 4 party members. That's domineering and evil, but it's not killing anyone.
And is age and lengthy solitude supposed to have affected his character? Even a totally evil BBEG might change in part given a hundred years or so of solitude.
I just don't think he's anything like a gloating Sarevok drunk on his own power with a god-like mission at hand. Unlike him, Kethric is motivated by vengeance or twisted redemption, has known defeat, and has had power for a length of time. There could be a touch of nihilism about him too.
