"Epic" is an amazingly exaggerated word to describe the Star Wars script.
"Epic" used to mean long narratives like Beowulf or the Iliad. Now it's a Dorito flavor.
To be fair, they were trying to do an archetypal hero's journey type thing for Star Wars, which would theoretically put it into the category of an Epic. Wasn't Joseph Campbell of _Hero of a Thousand Faces_ part of the story development team for A New Hope?