While its easy to see folks getting all excited over the possibility of one of these concepts being used, then speculating on the significance of the images -- these are failed concepts, folks. They never went beyond the stats done here.
The FAILED AD CONCEPTS were done by (or under) Olen Earnest for David Weitzner. David and I had major disagreements. In fact, I disliked him -- especially post STAR WARS as he claimed he did work I did. I thought he had no clue what STAR WARS was all about, but after the successful release of STAR WARS, Weitzner crowed about his importance in making the film a success. Needless to say, I thought he was an ass.
You can see from the FAILED AD CONCEPTS and this memo below that Weitzner had no clue how to market STAR WARS. They were looking for a hook, basing it on successful past campaigns like 2001, Midway (1976) or the multi stars' format of Poseidon Adventure, Earthquake, etc. It's a shotgunning method basing a campaign on past successes that was used by a lot of people who had no clue what they were after. The only one at Fox who had an inkling how to market STAR WARS was Johnny Friedkin. Johnny's support really was an important element in successfully marketing STAR WARS. Johnny didn't get along with David either.
Here, you can see how the style of the successful MIDWAY Campaign was used for STAR WARS by clustering the characters in the center of the frame. The cluster is set up in a central pyramid where the stars are the largest, surrounded by the supporting characters, then the minor characters, in descending order. You position the eye to see who is the most important, next most important, than on down. It's a quick read for the audience.
Prior to STAR WARS, the big theatrical science fiction film was Kubricks 1968 film, 2001. The Vader silhouette could not be used because it referenced 2001, leading the audience to think STAR WARS would be derivative, plus, the general audience view of Vader's helmet was it had a Nazi reference. You have to remember you're looking at these ad concepts 40 years after the fact, with the eyes of a fan who knows what the STAR WARS symbols represents.