Prediction: Daenerys sets sail to Westeros
The question isn't if, but when. Daenerys' eyes have been set on the Iron Throne from the very first episode, and now that she has several armies at her disposal, a fleet of ships, and a squad of trusty advisors, plus Varys already doing prep work for her back in Westeros (maybe in Dorne? That subplot has to lead to something, doesn't it?), she finally has what's needed to invade Westeros.
With the way Season 6 has played loose with time, I don't see why Dany won't be setting sail at the beginning of "The Winds of the Winter" and catching her first glimpse of Westeros by the end. Yes, a few issues make this proposal less than a certainty. Euron could show up last minute looking to pick a fight, for one. And the show's pacing may not allow for it -- after that display of dragon fireworks in "Battle of the Bastards" and a lot of other stuff to unpack, this episode could be light on Daenerys. But, c'mon, the Queen of Dragons has to get to Westeros eventually. Let's kick it into gear before Game of Thrones sets sail for Season 7, OK?