The Realm of the Elderlings is secretly ruled by cats
In the short story "Cat's Meat" (Published in the collection The Inheritance), Marmelade the cat states that cats can talk to whoever they please, whether they're Witted or not. He is also shown to directly influence people's thoughts. So it must be cats who are the real masters of the world. Not humans. Not dragons. Everything that happened in the novels is nothing more than a giant Gambit Roulette run by cats. Fitz will die in the Fitz and the Fool trilogy
In the first two trilogies, we knew Fitz had to survive because he was narrating the books. However, Fool's Assassin adds chapters narrated by his daughter Bee, leaving open the possibly that he will die and that the story will be concluded by Bee. Given that the epilogue of FA foreshadows dark things to come, it wouldn't be unlikely. Fitz dies after a fashion. The Servants infest his bodies with the same worms that killed one of Beloved's agents in the first book. But he manages to Skill-carve himself a "dragon" in the form of a wolf. His soul, that of Nighteyes, and the Fool's spirit end up bringing it to life, finally joined as a whole being. Which, deep down, is what all three wanted.