Whenever I read the books (my favorite science fiction of all, by the way), I always imagined the Baron as being bald, about three times as fat, and hovering low enough to the ground to use his feet for propulsion, but otherwise you have it just about dead-on to my imagination. Good job! And very well-drawn, too.
Considering Baron Harkonnen and his enormous girth, and I understand Dune came before Star Wars, the chief Harkonnen looks like a cross between Darth Vader (sans the mask) and Jabba the Hutt (because he is morbidly obese). Good work!