The first Star Wars was good. A little long and pokey (and Han Solo did shoot first). The second was really good (having not been written by George Lucas). The third was silly. The forth was a mess. I have a vague recollection of watching the last two on TV and rolling my eyes a lot.
The major problem (IMHO) with the most recent three was a lack of a Han Solo character. You need a character who doesn’t entirely buy into Lucas’ leaden earnestness. Until, of course, he does. There was no “are you kidding?” character in the last three films. Jar-jar Binks was just infantile.
I’m sure JJ Abrams will do a fine job (especially with Michael Arndt writing). But it’s inevitable that there will be some sort of backlash against the necessary improvements/excisions/mercy killings they’ll make in the service of coherence.
Let’s just hope JJ goes easy on the lens flares.