George Lucas-1977 Rolling Stone Interview
"Star Wars is about 25% of what I wanted it to be. It’s really still a good movie, but "it fell short of what I wanted it to be.
We did a lot of work but “there is nothing that I would like to do more than go back and redo all the special effects, have a little more time”.
http://starwarz.multiply.com/journal/item/10/1977_Rolling_Stone_George_Lucas_Interview
Mod Edit: a working link to the above article by Paul Scanlon, dated May 7th 2007, re the 1977 Rolling Stone interview, can be found below:-