Retro livery is such a great idea. One only need to look at Miller Lite to see how much it can do for a brand. The logo used until a few years ago was terrible. It had no character. When they went back to the old school "Lite" logo, it was a smash hit. How excited would you be to see a logo like this on your plane?
United would do well to find some classic designs and start putting out "throwback" planes. People would love them.