I agree with this part, but I don’t see Cersei/Jamie getting involved with the Sam subplot. BTW, Sam is the stand-in for GRRM, so I think he needs to survive to write the history that the 7 books (someday…?) will be. Sam will discover something about dragonglass, like how to make more. He may discover Jon’s parentage also. (Unfortunately, Gilly is not critical to the future plot…)
And, yes, I agree that Jamie will kill Cersei (just before Arya gets to her). Cersei thinks the younger brother in the prophecy is Tyrion, but will be surprised that it is Jamie–who will be a kingslayer and a kinslayer. Brienne will later kill Jamie in battle.
The 3 Targaryens–Dany, Jon, and Tyrion–will ride the 3 dragons in Season 8 to defeat the Night King. If we are lucky, there will be an ice dragon to even out the fire/ice power, but Fire will win.
I like the Sansa and Tyrion getting back together, but I’m hoping Littlefinger dies this season.
Once Bran goes through the Wall to get to Jon, the magic is defeated and the White Walkers will get south of the Wall this season. Depending on the special effects budget, the Wall may even come tumbling down.
Lots of bloody battles this season between ships/Ironborn, dragons, Dothraki, Lannisters, etc. Lots of people we like will die.
Who will win Cleganebowl? I hope the Hound, of course.
If Arya is Lady of Winterfell, who will she marry to produce an heir? Gendry–uniting house Stark and house Baratheon?