There is a lot that needs to happen still in this single episode:
1) Brann's story needs to be finished. They showed him being able to change things in the past twice (Hodor and yelling at young Ned), so I'm sure something will happen with that. Shame Brann hasn't done anything this season yet, because he could've prevented much of events that took place. This might intertwine with Tyrion's ending, since they "talked". Also the whole Jaime might still be alive theory (since he got no farewell on social media nor did he get his "death" interview) would be very good to salvage his character-arc somewhat. All the remaining characters need some sort of closure, not just the main cast, but the likes of Yara Greyjoy and Bronn as well. What goes on in Essos etc?
2) They need to take care of Daenerys. Killing her isn't really an option because all the Dothraki are her bloodriders so they'll have to die too, and Drogon is not letting anyone hurt his mom. I doubt Westeros has enough strength left to fight her, so either she fixes everything (Brann's time-travel can work here) or leave for Essos peacefully and maintain the peace she brought there as redemption for her crimes. ... Or she burns everyone left in Westeros, but that isn't bittersweet ... . Jon hasn't done anything for the story this season, and the Lord of Light brought him back for a reason, which apparently had nothing to do with the Night King (he can't be brought back to kill Daenerys because if he stayed dead, she would not have become the Mad Queen in the first place). Maybe he's the one that goes back in time, keeping his secret or something.
Lets hope to end on a positive note. The last couple of episodes were a bit subpar, but no need to complain before it's all over. There should still be a plot twist coming, to explain everything. Unfortunately, with only 75 minutes left, it will probably feel rushed again, but I hope they'll take their time on some scenes. We'll see tonight if I might sign that remake petition or not xd