Well, Yhwach is in Royal Dimension and on his way to dethrone the Soul King, something which Aizen couldn't come close. His army also did considerable damage in SS, Yamamoto being one of the chief casualties. He also has historical significance as far as we know, he even seems to be acquainted with the Royal Guards. On the other hand, arguably Yhwach lacks the charisma Aizen had, and I guess Aizen's arrancars such as Grimmjow or Ulquiorra made a stronger impact on the readers.
So what do you think? Who is the better villain overall?
So what do you think? Who is the better villain overall?