Beg your pardon?
Like every good director, George Lucas
I beg to differ - he is horrible director and the dog's breakfast known as Star Wars Episode 1 is a testament to that. So is the complete and utter destruction of the pace and the action in Episode 4 after he vandalized it.
He is a businessman and good at monetization of his wares through product placement and merchandising. Director - gimme a break.
The best star wars movies are the ones without him - Episode V directed by Irwin Kershner and the people Fox put to do the original IV where he should have never got the credit as he was under tight control not to damage the goods.
As far as audio, you have forgotten the Episode IV release conditions. During the first month (if memory serves me right) Episode IV was restricted to be shown ONLY in the Dolby enabled cinemas and it was the first film to fully leverage the format. The work was already done and it was not him who made the decision to force the issue and insist on the cinema having surround sound. It was Fox.