It would be a time saver if you could create a “Smart Playlist” that would allow you to pick multiple TV series and anytime there are unwatched episodes of these series that series would show in the “Smart Playlist”. After each episode is watched that episode would be deleted from the “Smart Playlist” but the file would stay in the library and be marked as watched. Once all the available episodes for that series are watched that series would not show in the playlist.
With so many new shows dropping an entire series at once and the others dropping weekly this would make shuffling multiple series that you watch on a regular basis so much easier.
Then when new episodes of a Smart Playlist series are added those episodes would make the series reappear in the Smart Playlist and show the unwatched episodes available.