First off-Oberyn v. the Mountain is the best duel EVER WRITTEN OR FILMED, including non-fictional duels. (Best "duel" between three people is the climax of The Good, the Bad, and the Ugly. Best "duel" between one person is Tyler Durden v. Tyler Durden.) Sorry for going off on a tangent. I also enjoyed Strong Belwas v. the hero of Mereen just because it was very crudely humorous.
Since Melisandre has been brought up, I have an idea I don't think has been mentioned. Her prophetic abilities are pretty damn impressive-is it maybe possible that she is not deluded but has actually manipulated events to occur exactly as she wants them to? Could it be that she has been playing Stannis, claiming to aid him while intentionally sabotaging him? She seems to be able to see multiple futures-it is possible that she had seen Stannis and his "duty" and "honor" getting in the way of the War for the Dawn UNLESS he was too weak to muster opposition to whatever force she supports, while still keeping him strong enough to support her real hero-Jon Snow Stark Targaryen Ahai. Honestly I'm just playing devil's advocate, but it's something to think about.