The chapter 76 is showing us how Eren with the help of the new weapon and his team is capable of winning over an armored titan.
This is an amazing feat.
So how could the future look like ?
The balance of power is shifting right now
Winning over the armored titan is a tremendous feature as such, especially after winning against the giant monster titan (the hidden king). If the survey Corp survive on this arc mission; which means
1 - come back alive; 2 - with Eren and his power; 3 - having been capable of evading or repelling a titan tribe leader.
Then what next ?
How will the future look like ?
Will they :
Defending their land ?
Their next aim could be :
1 - learn to control the mindless titans; 2 - use the titans control power to rebuild their defense and defend their land
I mean, their ability to defend themselves will have grown tremendously, to the point where they can attack the titan tribe.
Bringing war to the titan tribe ?
Or it could be :
1 - learn to control the mindless titans (to make it safe in titan land); 2 - finding out where the titan tribe is living; 3 - attack the tribe, while commanding titans.
Trying to make peace ?
If the knowledge over titan shifting has been shared, then the other option could be:
1 - learn to control the mindless titans (to make it safe in titan land); 2 - explore where the titan tribe live; 3 - try to make peace ?
Why is there no peace treaty in this war ?
There no negociation YET between both armies, between regular humans and titans shifters.
The balance of power was broken
The fact that the hidden king held secret is knowledge about titan shifting and the past made it impossible to find a peaceful solution. Keeping the humans in the cities ignorant was a mean of heldong control over them. This was a sinful choice which almost led humans to self destruction.
Now that the hidden truth came out and that the humans held prisonner could free themselves from this mental and social slavery, a ray of hope is appearing. But still...
I mean, both parties are intelligent and speaking. Both are human, beneath the appareance. Also, both have now the power on a titan shifting. And soon both will be able to command over mindless titans.
Also the king was taken out, by the survey corp. And now a new regime is in place.
And there is no memory of the past, from the regular humans side.
Last but not least, both party where already capable of talking together, and even spend long period of time together (Annie, Bertold, Reiner) and they liked each other.
All of that added, this a major shift in terms of awareness and relationship, at least within the young generation.
So there is already a potential for a future peace.
Key elements of a future peace
The key elements for the future
1 - surviving the actual ordeal against the titan leader; 2 - learning how to control mindless titans; 3 - finding a way around the titan leaders, who seem stuck on killing/hunting down regular humans.
Surviving the actual ordeal against the titan leader
Winning over the armored titan is still not enough.
Now, they have to face the titan leader himself, ordering mindless titans around...
Eren's learns to control mindless titans
Obviously, the power to control over titan is a key element for regular humans to control themselves.
Now a few questions are still open.
What does Eren lack to control mindless titans ?
How does the mindless titans responds when two titans shifters are struggling over their control ?
What is the limitations in terms of this control power ? How many titans ? For how long ?
Survey Corps move the war to the Ape titan's tribe territory
Of course, there i an issue with the Ape titan... The actual arc will probably be a good assesment on how difficult this will be... He obviously does NOT care at all about regular humans... nor the people of his tribe. But the survey corp was already capable to overthrow their hidden king, to win over Annie and Reiner, so why not winning a battle against him ? May be not the first time. But later on, why not ?
The more data they collect over titans and the more they test and practice, the stronger they become.
Why is the consciousness of both parties not changing faster ?
Beside the issue with the titan leader, there is at least 3 factor missing for peace.
The lack of knowledge regarding the titan weapon
Regarding titans, the lack of knowledge is still a huge weakness on the regular human side. Therefore, i guess that finding Eren's father journal is being an important key stone.
The lack of knowledge regarding the underlying conflits
The assessment and awareness of both parties leaders is still lacking. In fact, both know almost nothing regarding the other party issue. For example, why is this urge to destroy humans from the titans shifters side ? There is obviously one or more underlying conflict from the past, hidden or half forgotten. But still active...
The lack of relationship with the other party
There is still no communication channel open between the 2 parties. There was one, but it was unintentional. How could this change ? And when ? Annie is frozen in the crystal. Reiner should be killed. There is only Bertholt and Ymir left. And Ymir is an outsider to the titan tribe. So is the opportunity of this connection channel going to close again ? Or not ?
The actual arc is no longer about winning over one powerful titan, but truly about winning a position of safety for their kingdom.