Originally Posted by
Jastall
The only one I'd like myself is a Robert's Rebellion spinoff. It would allow us to see characters such as Ned, Robert, Rhaegar, Hoster Tully and Jon Arryn in their prime, and the period is plenty documented enough to not allow the showrunners to mess up too much (if only because the situation at the start of Season 1 is more or less the same as in the start of A Game of Thrones). There's political intrigues, a mad king, tons of pathos and character drama, a hugely climatic battle culminating in the single most famous, important and emotionally charged duel ever, and a bittersweet ending veering on the bitter. The thing almost writes itself, really.