I hadn't thought a lot about vintage pieces, but your raise an excellent point that the vintage world is a wonderful hunting ground for classic pieces that reflect the ethos of their creators. Just to look at any of the pieces that Tick-talk (Dean) or Dan Shao show here illustrates that there are wonderful, sincere (as you say) pieces that are not stratospheric in their cost.
I also liked your split between "sincerity" and innovation. I'm not so sure that for me it's about innovation per se, but I do admire solutions that contravene conventional wisdom. So, Kari's decimal repeaters, Volker's hard-wiring of the minutes hand to the seconds hand, and so on do get my attention, just for the "why didn't someone else think of that?" factor. I loved your examples of the functional innovations of the past, though -- for me perhaps it is this idea of "functional" innovation vs. show-offy newness that appeals. Again, of course, one man's function is another's frill...
Thank you for your very thoughtful input to the thread -- I do appreciate it, and learned from it.
Best,
Gary