Well, Naruto could face old enemies who thought he was gone for good. They might be shocked when he returns seeking revenge. For example, if Orochimaru was still causing trouble, Naruto would use his newfound knowledge and strength to take him on.
Another possibility is that Naruto's return for revenge could spark a new era in the ninja world. His actions could inspire other oppressed ninjas to stand up against their oppressors. His journey for revenge could turn into a movement for justice and equality, completely changing the power dynamics in his former world.
He might have to deal with the moral implications of revenge. Naruto has always been about forgiveness, but in this fanfiction, his past traumas drive him to seek revenge. He could struggle with this internal conflict as he tries to exact vengeance on those who wronged him. Maybe he meets an old friend who tries to convince him to choose a different path.
Well, Naruto might find that his old friends have changed a great deal. Maybe some of them have new powers or have faced different challenges in his absence. He could also discover new threats to the village that he needs to deal with right away.
Perhaps Naruto returns to find his former world in chaos under the rule of a tyrant. Remembering the pain and suffering he endured there, he decides to take revenge by overthrowing the tyrant. He uses his ninja skills and his ability to inspire others to build a resistance.
It could be that Naruto returns to a world that has changed a great deal in his absence. There could be new political situations in the ninja world. For example, new alliances might have been formed between different villages. Naruto, being Naruto, would probably try to bridge any gaps or misunderstandings. He might also discover new talents among the younger generation of ninjas. He could take on the role of a mentor, just like some of the people who guided him in the past. His return could also spark a new era of peace and cooperation in the ninja world as everyone looks up to him as a symbol of hope and strength.
In this fanfiction, Naruto might reunite with his old friends and sensei. He could show off new jutsus he learned during his time away. Maybe he'd also face new threats to his realm that only he can defeat with his unique skills and experiences.
There's a good chance he meets Kakashi first. Kakashi was his mentor and they have a strong bond. Kakashi might be out on a mission near the place where Naruto returns, or just be around the village doing his usual thing like reading his book at the training ground.
In such a fanfiction, Naruto might return to Sakura with newfound powers. Maybe he comes back after a long and dangerous mission. He could finally confess his long - hidden feelings for Sakura, leading to a romantic reunion.
Well, perhaps Naruto comes back with incredible powers. He might be seeking revenge on those who wronged his village or his friends. Maybe he was betrayed in the past and now he's back to make things right and punish the traitors.
In the fanfiction, Naruto's return from training could also lead to a change in his relationships. His friends might be in awe of his new strength and some might even feel a bit of distance as he has become so much more powerful. Also, he could use his new abilities to protect the village in a more effective way and gain more respect from the villagers.
In this fanfiction, the Naruto family might be welcomed back with great joy. The villagers could hold a big celebration to honor their return. Naruto, as a hero, would finally be home with his family in Konoha, and his kids might start exploring the village that their father has so many memories of.
In this fanfiction, Naruto might finally have an emotional reunion with his parents. He could share all his adventures, growth, and the pain he endured. They would likely be proud of how he became a great ninja.