combining the best features of all the released FF games. For me a simple concoction would be a mixture of FFXII's combat system, side quests (hunts FTW), and open worldness, FFXIII's graphics, and how each character acquires and uses Espers/Eidolons/summons, FFIX's story and characters, and FFXII's music (strangely its the first one I played years back but its the only one I can remember the music to).
Go.
Go.