Something that got me thinking was the description of how some of the dual-deck VCRs (like the go-video decks) are able to make such higher-quality copies. The machine directly copies the FM signal on the tape, rather than converting to RF, or composite, or whatever and then converting back again. The results really are significantly better than anything else I've seen. Maybe something like that could be done with laserdiscs, too. If there were some way to digitize the signal as soon as possible in the path from laser to screen, maybe you could capture the maximum, definitive quality stored on the disc.
It would take someone smarter than me to do this, however.