Media migration was easy enough. I had to move some "extras" around, and I switched to #TheTVDB's metadata to get away from #TheMovieDB's bad opinions, but I was able to keep both media servers running from the same media folder until I was ready to fully switch.
("TMDB's bad opinions": specifically their guidance that shows with multiple "segments" should represent each segment as a whole episode, i.e. making every episode number wrong for a show like Urusei Yatsura. There are other problems with their metadata, but no point in polishing a turd.) [2/]