When the stitching starts to show

At this point, I’m starting to think the only real fix is to strip everything down to bare wood, which sounds like a nightmare for both time and budget.

Honestly, I’ve wondered the same. Have you looked into using a heat gun or infrared paint remover? I tried it on a small section of trim—took forever, but the results were way better than just scraping. Still, it’s a slog. Ever thought about replacing just the worst boards instead of stripping everything? Sometimes patching with new wood in the worst spots buys you more time than another layer of paint.