Hear me out for a second: Leaf gets destroyed.
That's the price of our failure. Just Leaf, we can say Mari flinched away from the proliferation button at the last second just like Hazou flinched away from activating the Superchiller. Itachi descends on Leaf like a wrathful kami and without Hazou or Orochimaru there to defend it there's no hope. Leaf-nin scatter into the wilds, Leaf's institutions are shattered, and as far as geopolitics is concerned Leaf transgressed AMITY for the final time and now no longer gets to exist.
Notably, this does not kill all Leaf-nin. The groups that scatter, clans most likely, hole up in secret places across Fire Country, knowing that they can't return to Leaf without getting hunted down. So Ino's still alive somewhere out there, and the Nara didn't get wiped out and trigger whatever unfathomable consequences that allegedly entails. But Leaf still ceases to exist as a geopolitical entity, and the rest of AMITY descends like vultures on its territory to take it for themselves.
Hazou, of course, still goes through an afterlife arc and claws his way back into reality. Time dilation is not needed here, arriving back in the EN somewhere between a month and a year from now would still be fine timeline-wise, which smooths over one of the bigger contrivances of this route.
But why is this desirable in the first place? It's simple: as I was talking about before, the quest was contorted into an unfun researchmaxxing state because if we didn't Leaf would die. The threat of Akatsuki was too strong, too imminent, and nobody else could feasibly protect Leaf. That forced our hand, made us bite the bullet again and again and again, even if we'd rather go hunting crabs for chakra metal or something.
But what if Leaf... wasn't? It can't be in danger if it's already destroyed. The people who were in it, they either survived or they didn't, living in secrecy or dying in Leaf's defense. When we stumble across an enclave of survivors we'd want to protect them, but they're already protected by secrecy and in a stable state: they can wait until we're in a good position to make a move. We'd want to take revenge on the Akatsuki, but they're also in a stable state and we can wait until we're in a good position to make a move. We can afford to follow Orochimaru's advice, running around power-seeking in fun and engaging ways, the right balance of research and adventure, and only then take the world by storm and bring Leaf back from the ashes.
And as for why I said "the price of our failure"... I haven't been looking at the situation this way myself, but there seem to be a lot of players who feel that because we lost here whatever solution we arrive at should still carry some of that loss forwards. That our death should still have consequences, still make us suffer, even as we weave a scenario in which Hazou's story gets to go on. I, personally, am intrigued by this idea mostly because it sounds like it would fix a lot of the incentive structures of the quest, but it also undeniably counts as a major loss for Hazou and his goals, which would make it and options including it more palatable to those among us who want us to carry the scars of this moment forwards.
I'm also not married to it, to be clear, it just crystallized in my head now after a day or two of idle thoughts, but it seems reasonably plausible and surprisingly beneficial for the quest. Sometimes you need to prune a few branches to keep the tree healthy, after all.