Interesting points. I can vouch that this is one of the most time consuming tasks ever. My father purchased a scanner perhaps 8 years ago with the intention of getting his slide / negative stock scanned. Thousands of images. He gave up after a couple of hundred as it was simply too tedious.
Also, the scans he made on technology from 8 years ago are no match to what can be achieved today. So what is he to do? Re-scan again? I would expect that today's scanners are up to the job of making scans that will be of sufficient quality for discerning home use so perhaps now is the time for me to get into the market.
One question: does anyone know of a scanner which will handle APS cartridges or opened negatives? I have a dozen or so rolls of these from more recent times that would be useful to have scanned.