So try to follow my logic here and if you can tell me where I'm wrong, because I'd like to enjoy the climax of this series but in my view I simply can't because there's no logical way they can take the series now that would make in universe sense:
1. The Others threat for storywriting purposes was basically just a clock, they represented the pace at which the story must unfold because they were the impending doom forcing action on the protagonists to prepare for their coming. The reason the north couldn't take care of Cersei first before taking on the Others, the reason they had to worry about stocks of food to live through the winter, was because they ran out of time, the Others breached the wall and now they're here.
Now that the Others are no more, there's no more clock forcing action on the protagonists, time is no longer an obstacle they should have to worry about. The north could logically simply hole up in the northern Kingdoms for the next number of months/years (Winterfell/the Eyrie/the Stormlands/the Iron Islands), recovering their strength and replenishing their food supply. They could even spend the time bolstering their fighting forces by sending envoys back across the sea for reinforces from all the city's Dany liberated.
The point being barring Cersei sending armies north (the antagonists), there's nothing forcing the northern alliance (the protagonists) from jumping into another battle while they're at the disadvantage numbers wise. Should they decide to (which the preview of next episode I guess hints at), it would either be intentional poor decision making by the characters to further character growth (even if in a negative direction), or simply bad writing. There's no logical in story reason for the protagonists to rush into conflict with Cersei. Now that the Others are defeated and "Winter" is over, there's no rush.
2. Bran and Arya's powers are giant plot holes for the remaining supposed conflict. Bran can literally see everything that's ever happened anywhere, he just has to know what he needs to be looking for in his memories first, otherwise he's as close to omniscient as you can write a character. Arya can kill just about anyone with her combat skills (even apparently magical zombie Sauron), and can more importantly magically disguise herself as literally anyone. These two plot breaking powers are just barely kept in check suspension of disbelief wise because they antagonist is just as magically powerful as they are, right up until the writers decide to off the big bad halfway through the final season, leaving just an often drunk mortal woman as the final boss.
They've established Bran can view any event that's ever happened, anywhere they happened, and can actually even influence events retroactively should he choose to. So at the bare minimum, they should have the absolute best possible intel for any battle strategies needed in a hypothetical battle against Cersei's army. Tactically they should have the biggest upper hand you could possibly have, meaning, regardless of how they try to end the series conflicts, if even once the protagonists are surprised by something leading to a loss in battle, it's a plot hole, because Bran should've seen it coming.
They've established Arya can sneak into an enemy castle filled with every member of house Frey, and have the stealth capabilities to not only secretly maneuver her way to the head of the family in his own castle, kill him, take his place in disguise, and poison all the food/drink served at banquet that same night. All of these things are established reasonably within her ability to do. So logically, the north wouldn't even have to send an army south to defeat Cersei, and as I said they should logically be in no real hurry barring Cersei sending an army north. Simply send Arya to King's Landing, have her kill someone with the ability to enter the gates (a peasant, a guard, whoever it doesn't matter), and by process of killing someone new, disguising herself as that new person, continuously until she's able to take the face of someone with access to Cersei's presence (Qyburn is the logical answer), then when she's alone in her chambers, shank her in the stomach, and the war is over. There's no logical reason any of these events couldn't happen by the show's own established logic from prior events, other than the show would be over to easily. In other words, the writers wrote themselves into a giant plot hole if they're trying to play off Cersei as a satisfying final antagonist to the story, she logically shouldn't be a threat at all.
3. The north still has 2 living dragons based on the next episode trailer. Aegon the Conqueror, the character that kicked off the events the show and setting is founded on, along with his two sisters and their combined 3 dragons, defeated every army of then Westeros by themselves, because dragons are the medieval equivalent of nukes. The north still has 2, and King's landing is just one kingdom.
So take into account Bran's omniscient knowledge, Arya's deus ex machina ability to kill just about anybody as an ultimate assassin, and 1 dragon logically being enough to defeat any army let alone 2 dragons, and there's no logical reason Cersei should pose any threat to the protagonists.
And we're supposed to derive any compelling drama from the remaining episodes why exactly? It just doesn't seem to make any sense to me, but I'd love to be proven wrong.