marioxb said:

Even as a kid, I always thought that Vader was higher in rank than any of these "regular humans".

I think a lot of people feel that when they watch the film as children because Vader is a major character and all these Grand Moffs etc are minor characters but when you examine the text of the first two films it's clear Vader is an instrument of the Emperor, good at what he does but not the Emperor's second in command as he became in the PT.

Lucas became increasing simplistic in writing his characters the more control he got over his fictional universe.

Boba Fett went from being a bounty hunter to a body guard/mini-boss for Jabba just as Jengo and Grievous would for Dooku in the PT. Ironically the cartoons based on those films were less cartoonish in the depth it gives it's characters.