One bit in the Making of ROTJ that's pretty enlightening as to Lucas' overall priorities is the story of Dermot Crowley, who played General Madine.

Crowley showed up to wardrobe fittings and was repeatedly urged to wear a fake beard. Essentially, he was told he must wear this beard. So he agreed, but he wondered why the costumers were so insistent. Later he found out that a "General Madine" action figure had already been molded by Kenner--and the figure sculpt was bearded.

(I'm sure this anecdote has been told before, but I would hardly have expected it to make it into an official LFL book!)