One of the reasons I like SW so much better than ESB are the settings. In SW, we essentially have a planet with large natural landscapes, a huge space station, and a lot of outer space. There is more diversity on Tatooine than in all of the venues of ESB put together. Most of SW it takes place in big places where there is a lot to explore. Ben takes Luke to increasingly distant destinations. By contrast, ESB takes place in mostly confined places - an ice planet where everyone has to stay indoors, a rainy dank planet, the inside of an asteroid, and rooms inside of a city. SW seemed expansive and the unveiling of a universe for a farm boy, whereas ESB always felt claustrophobic to me.
The SW universe also started shrinking with ESB and ROTJ, with Luke's father being Vader, etc., and lack of introducing any significant new characters that weren't already alluded to in SW. (Yoda being the one, signifcant exception - that puppet single-handedly transforms the movie from a bore to a classic)
As good as ESB is (and I don't mean to imply that it isn't great - only that it isn't as great as SW), I think it missed its chance to continue expanding our view of the universe, rather than shrinking it. I could imagine SW going on forever with writers using their vision to continue adding new vistas, new factions, etc. Instead, by making the "saga" so closed and wrapped around itself, they have effectively killed it as a venue for really new ideas.
For example, imagine instead if in ESB we had learned that the Empire was just one of many factions vying for control of the dark side. Or if there were galactic rulers beyond the ones we have met. Or if other races discovered other ways of using the force. Or, what if Luke fell in love with some fascinating woman Sith? The possibilities are (were) endless.
If Disney approaches Ep.VII/VIII/IX in that way, they could potentially reopen the doors to more SW. If they keep trying to build upon the "saga", I think that interest will dry up quick. At least mine will.
