Let's use another great sci-fi 'verse to provide context on why the "frontier" is not a necessary backdrop for good Star Wars, but rather, was a convenient short-hand for the rebel alliance who had to live there.
In Firefly, the browncoats lived in the outer planets (the frontier) because they wanted to be far away from the Alliance (ironic, I know) in the central planets. This embodied the separatist/individualist spirit.
But we needed aspects of the Alliance to show a sharp contrast to what the browncoats fought against and lost to. Some of the best moments in Firefly came from Ariel or Trash, which were set very much in the Alliance world.
So how does this relate back to this wonderfully produced (hey, nice commercial!) but woefully short-sighted plea from some group who claims to speak for the "fans". Well if you ONLY watched the original trilogy, you would think that Star Wars was all about the frontier. After all, there was no Coruscant and the moments in the Death Star were really limited in backdrop and exposition.
Then again, if you've read any of the canon books or played any of the games, you will know that dozens of storytellers have expanded the Star Wars universe, giving it beautiful color and context around the edges that 7-8 hours of the original trilogy couldn't possibly cover.
Sure the prequels were bad, but they were bad because they're bad movies. I certainly don't agree with the de-mysticism of the Force, or Jar Jar, or the implicit racism, or Han not shooting first or Mannequin Skywalker's casting, but let's be honest, those are just bad movie dialogue, story-telling and direction. These are problems every movie has (have you seen Howard the Duck?)
The reason the prequels were NOT about the frontier because it's really a story about Obi-Wan Kenobi, Anakin and Palpatine, whom coincidentally, all lived in Coruscant, a city. The original trilogy were about Luke, Han, Chewie and Leia and they all lived in the frontier, away from the Empire. Let's also not overlook the fact that Threepio is comic relief and the Ewoks are cute.
In conclusion, let J.J. Abrams make a good movie and let's not put artificial boundaries in because we have some misguided fanboy adherence to rules that were made up to begin with. If we listened to the fanboys, we'd never have Hugh Jackman as Wolverine, Heath Ledger as the Joker and there would be 30 minutes of Tom Bombadil singing in the Lord of the Rings.
TL;DR: Let JJ Abrams do his job without constraint and Firefly rocks.
They had great actors, so it must have been the writing that sucked, not the actors.
TL;DR: actors are only as good as the environment you give them to work in.
The prequels were horribly acted, but the attempt to make a classical backstory to illustrate the fall to a romantic frontier was, to me, admirable. The Prequels were set in high society (city) to show the great classical culture which valued learning (libraries) and articulated methodologies to master the world around them (real understanding of the force).