I am a big fan of the bare metal silver livery of old AA I also wish they had brought it back on retro 77W. I understand that with aircraft fuselages going to composites, like 787s, the bare skin of the aircraft is not a polished metal look anymore. But I remember more than 10 years ago, on a news release that AA worked with Alcoa (an aluminum company) and made a paint containing aluminum, which gives a polished metal look.

I thinks this retro 737 and 757 looked so nice.

Did you know that American had a 757 Astrojet? - Real World Aviation - Infinite Flight Community

File:Boeing 737-823, American Airlines AN0171406.jpg - Wikimedia Commons