Here's how I think this season will wrap up:
The North - Snowbowl in Episode 9, Jon and Sansa will retake Winterfell with LF's help
Meereen - The Dothraki horde kill the masters on land, the Greyjoy good guys will take care of them by sea. Yara/Theon offer their services to Dany. The Greyjoy fleet + the slaver's fleet takes everyone on their way to Westeros. (finally)
Varys - Going to Westeros...probably meeting with Dorne to set up a nice welcoming party and an additional army for Dany when she arrives.
Arya - Starts on her way back to Westeros...She's been in the dark as to what's happening since she left, so probably heading to Castle Black to find Jon but sees Bran instead?
Sam - Goes to learn about White Walkers at the Citadel
Bran - Arrives back at Castle Black in time to see a White Walker siege of the Wall
King's Landing - I think this is where the **** hits the fan in Episode 10. Jaime comes back with his army just in time to see Cersei attempt to burn the whole place to the ground with wildfire. He has flashbacks to when he had to make the choice of killing the mad king, but in the end decides to rescue Cersei instead. Many casualties including the HS, Loras, Margaery, and Tommen. The ashes over Kings's Landing that Dany saw in her vision turns out to not be from Dragon fire, but from wildfire. Cersei and Jaime escape back to Casterly Rock with the Lannister army.
Brienne and Pod - Heading back to the North in the aftermath of the Snowbowl
So pretty much the various storylines have consolidated back to a few locations in Westeros to set up Season 7.
The North - Jon, Sansa, Bran, Arya, Brienne, Littlefinger
Westerlands - Jaime, Cersei
Dorne - Dany, Greyjoys, Tyrion, Varys