I agree act 3 of rots can be a bit sudden for Anakin. The rots novel has become my favorite telling, makes his turn more believable.

Ive seen your take on the difference between CW and PT Anakin quite a few times. This is because CW shows Anakin at the most stable part of his life, and has much more time to show it. With the films we see glimpses of anakins childhood, becoming an adult, and turning. All chapters of a story which bring a previously unseen aspect to Vader's character.

I guess unseen is the world I'm looking for. If Ewen McGregor's obi wan turned out to be Vader, that would be completely unrecognizable. Rather Anakin's story is the tragedy of an awkward kid raised in all the wrong ways, hence becoming a cunning villain.