Traya tried to destroy the Force,
She would never have suceeded, so it hardly matters. She is the Lady of Betrayal, though, so maybe not.
Revan is insane and constantly flip-flops
The original Revan never flip flopped. He was a fantastic Sith Lord, and toned down on the evil selfishness too.
and Sadow got the Sith Empire destroyed through his own selfishness and incompetence.
I considered this, but ultimately I just put him up there because of his similar progressive political views aligning with the others.
Malgus also shouldn't be on their imo with his huge boner for constant warfare which is pretty awful.
They all do. And he would have made a much better Emperor than Vitiate, or any of the rest.