I've always liked the way the PT posters looked. The AOTC poster is my favorite of the entire saga. Too bad it depicts an epicness the movie can't live up too :p

I don't think you really added anything to the TPM and AOTC posters, but I liked what you did with the ROTS poster, if only for replacing that terrible image of Padme that was used on the original poster.

The ROTS poster has always been my least favorite. I don't like the images of the cast that were used and it always seemed a bit too crowded for me. And the composition is weird in that it kind of feels like it should be a landscape poster but not really. You are right in saying that Struzan was asked to put Vader on the poster after he was done with it, so that may have been part of why the composition is a bit forced.