Game Of Thrones Season 6 Finale: 5 Hints Lady Stoneheart Will Appear
2. Almost Every Other Theory Has Been Confirmed

For all the misdirection, almost every fan-favourite theory levelled at this season (outside of the mind-numbingly stupid ones, of course) has pretty much come true. (The Cleganebowl possibility obviously hasn't, but that could still come later, which seems likely.)
We've seen massive hints at the Tower Of Joy flashbacks confirming R+L=J, Jon Snow came back to life, The Hound was revealed to be alive (as was the Blackfish), and then there's the hint that Tyrion may be a Targaryen (thanks to his not being eaten by the dragons).
That's not to say there weren't other theories that have dropped by the wayside, but season 6 feels very much like the season for confirmation, and there are so many individual hints that not confirming at this point would be ludicrous.