No, Joss Whedon is the same as George Lucas: they both work well with supervision. Compare the Firefly comics with the series, so many things are just out of character and wrong in the comics, because Joss was unsupervised.
Compare the old trilogy to the new: When George Lucas was doing the old trilogy, he was a young upstart with a niche artsy film to his name (American Graffiti). He was surrounded by people who weren't afraid to say "No, George, that's a stupid idea". Flash forward to the turn of the century, and you have George Lucas surrounded by sycophants saying "Yes, Mr. Lucas, sir! You're a visionary!"
Joss Whedon's Star Wars would be a bigger disaster than three episodes about Jar Jar.