Gendry is coming back. For what reason is anyone's guess. Maybe he'll be used to forge weapons with dragonglass. I just don't see any importance to his storyline other than he is Robert's last known living bastard. Maybe he is a love interest for Arya(if she's capable)
I would think that if BranRaven had no problem talking to his sister about her horrible wedding, he wouldn't have any remorse telling the girl who has been dragging him around for several years, "Oh hey, BTW, your dad isn't really your dad"
Speaking of that. Do we ever meet Meera's dad? Considering he is the only other living person outside of Bran that know's Jon's parentage. He might be necessary to prove that fact.
Jaime obviously lives, maybe we don't see him in the next episode, but he still has to kill Cersei (she is too paranoid of Tyrion to allow him to be the one to do it) And what does Cersei have to do to finally cause Jaime to snap and not follow her blindly?
The dagger will be used to kill Littlefinger. Beyond that, I'm sure it has some significance with the white walkers. Maybe it is the only weapon that can kill the night king. you'd think Bran would've figured that out by now though.
I thought the same thing about the dothraki. If Dany helps Jon, they better get the seamstresses working round the clock to get them some thicker underwear.
What's with Theon? Does anyone really care about his storyline any more? I'm guessing they're keeping him around so he can sacrifice himself for somebody.
How slow is the Army of the Dead? Everyone else zips around the continent, but it apparently takes them years to march the same distance Meera dragged Brandon in a few episodes. I can't imagine dead people need to stop for food or rest. Unless they are being calculating, waiting for something to break the magic of the wall.