I still maintain that, as amazing as it was, the final episode of Season 6 fecked everything up.Season 7 was still crap. It included possibly the worst episode of the whole show - episode 6, 'Beyond the wall'. It made absolutely no sense at all.
Dany is on her way with three dragons, Dorne in support and her army of Dothraki and Unsullied. Cersei just got rid of her enemies but at the cost of blowing up the church in a heavily religious city. How is Cersei going to get out of this muddle?!
The answer; she isn't. She's screwed. Either Dany toasts her in a second or the zealous peasants revolt.
Unless the writers start making crap up that goes against the essence of the show just simply to make things easier for a character.