Saw it this past weekend, completely agree with your assessment. (and I'm a young 40) I thoroughly enjoyed this time capsule flashback fantasy. I knew Rick Dalton's character was based loosely on a mixture of Burt Reynolds, Clint Eastwood, etc. And Brad Pitt? Looking more and more like Robert Redford as the years go by!!!!! Seeing Kurt Russell in there was a nice touch as well. There were some nice Easter Eggs to be seen, if you knew what you were looking at. For instance, one of the first shots of the studio parking lot when Rick and his stunt double were leaving, was shown panning out from the top. In the lot, you can see plain as day a red Ferrari 250GT California. It was an incredible car back then, and one of the world's most desirable and valuable cars today. ($25 million at auction). Younger people would know this car as the Ferrari in "Ferris Bueller's Day Off."
I LOVED the ending. Loved how QT pulled us in, expecting the absolute worst, but gave us the absolute BEST. A real "what if" or "what could have been" experience.
Brilliant.