Well, they could also change their own relationships. Maybe Naruto wouldn't be so alone as a child, and Ino could become a stronger ninja earlier. They might train together in ways they didn't before, using the knowledge of future jutsu and strategies. They could also influence the relationships between different ninja clans, like improving the relations between the Uzumaki and the Yamanaka clans.
It could be the same antagonists as in the original Naruto series at first, like the Akatsuki. But if Naruto and Ino change things, new antagonists might emerge. Maybe some ninja who were once allies turn against them because they fear the changes Naruto and Ino are making to the ninja world order.
Another twist might be Naruto going back to the time when the Nine - Tails attacked Konoha. He could potentially find a way to stop the attack or at least lessen the destruction. Maybe he could even change how the village views the Nine - Tails and those who are jinchuriki. For example, instead of fearing and ostracizing them, they could start to understand and accept them earlier.
Well, it could be about Ino being desperate to have Naruto return to the village or to her life in some way. Maybe Naruto has gone on a long journey or mission, and Ino misses him a great deal. She might take various actions to bring him back, like trying to convince others to go after him or using her own skills to find him.
Well, one thing that could happen is that Naruto, with his knowledge of future events, could easily ace the written part of the Chunin Exams. He might also be able to prevent some of the chaos that Orochimaru caused during the exams. For example, he could warn the proctors about Orochimaru's infiltration in advance.
Well, Naruto would be more confident. Since he has the knowledge of the future, he knows what mistakes to avoid and how to handle situations better. For instance, he won't make the same naive mistakes when dealing with his enemies or friends.
One possibility could be Luffy changing key events to prevent the losses of his dear friends. This would add a lot of drama and emotional depth to the story.
One plot idea could be that Ino goes back in time to the founding of Konoha. She could use her knowledge of the future to prevent some of the early tragedies that befell the village. Another idea is that she goes back to her own childhood and tries to change certain events that led to insecurities in her later life. For example, she might try to befriend Sakura earlier and avoid the rivalry that developed between them.
If Kylo Ren went back in time in fanfiction, he might try to change the events that led to his fall to the dark side. Maybe he would go back to a time when he was still Ben Solo and prevent himself from being influenced by Snoke. He could use his knowledge of the future to avoid the mistakes he made.