I dunno, S5 i was hoping would show the rise of the Scarlet Moon Empire, before its fall in S1. The Toran Republic has a lot of sites, history and potential.

Also, I heard there was a game/movie in which the story centered around Nash (from 3) and it showed a lot of behind the scenes stuff we didn't get to see in S2, like why Lucia and Sasarai join Jowy's side against the Dunan Army, and who exactly is Nash's "missus". Although that mystery isn't fully revealed, many speculate its Sierra or Theresa Wisemail of Greenhill. The Game/movie has a deeper history of who Sierra is, and the telling of how she lost her True Rune to the Neclord. Also it goes deeper into Clive and Elza's "feud". I'm curious to see this game/movie or whatever it is.