>>109863760The ultimate subversion I can think of that would still make sense within the plot is that the final boss of the show is Rapunzel herself.
We've had multiple threads of speculation about just what, exactly, is going to happen when Rapunzel unites the Sundrop and the Moonstone. Since that seems inevitable, what if the power proves too much for her and she goes mad? What if, instead of Rapunzel saving the world from Varian, Cass, or Zhan Tiri, the rest of the cast, including Cass and Varian, have to save the world from Rapunzel in the grand finale?