Naturally, the "universal average" is going to be based upon the "typical" OC interval. Most folks who do oil analysis are anal and will change every 3K. So, the numbers are going to be quite low.

Extrapolate the numbers out to 20K for a universal average for that mileage level. Those numbers look fine.

Where is it stated that iron of 72ppm is unacceptable? If this was a high quality synthetic oil, I'd have no problems with the number.

Tin was 5ppm. How can you have a problem with that?

Copper was 37ppm. Again, why are you concerned with 37ppm? The oil ran 20K miles!!!