Perhaps the relationships in the story are changed. His friendships with Sasuke, Sakura, and others might be altered. He could return and find that his friends have grown in unexpected ways, leading to new dynamics between them.
His character might become more mature. He has seen more of the world outside Konoha, so he could be more understanding and patient. For example, he might not be as quick to get angry at the villagers who once shunned him.
The fanfiction may change the pacing. In the original Naruto, there are specific story arcs and build - ups. However, 'naruto returns changed' might speed up or slow down certain parts. Maybe his return is rushed in the fanfiction, or there are more flashbacks and introspection compared to the original.
Another possible plot point is that Naruto's return changes the political situation in Konoha. He could have different ideas about how the village should be run after seeing other places. He might challenge the existing council or propose new policies for the ninja academy to improve the training of young ninjas. His influence could also extend to the relationships between different ninja clans in Konoha, either strengthening or straining them depending on the nature of his changes.
In some fanfictions, Naruto might return to Konoha to a cold reception because the villagers still hold grudges from his past. Maybe they haven't fully accepted his power or the chaos he sometimes brought. For example, they could be afraid of his Nine - Tails power flaring up again and causing destruction.
Definitely Hinata. Her love for Naruto is well - known. Sakura, too, as she has grown closer to Naruto over the years. Ino might also be in the harem. She has had her own moments with Naruto and her skills as a ninja could be an asset. And perhaps Karui from the Cloud Village. After Naruto's peace - making efforts between the villages, she could have developed feelings for him.
He would most likely meet his father, Minato Namikaze, and his mother, Kushina Uzumaki. These are the two main family members he never really got to know growing up.
Perhaps it could be someone from his own village that he never really noticed before. Like a girl who was always in the background but during his time away, she grew into a confident and beautiful woman. She could be someone who works in the hospital, and Naruto starts to see her in a new light when he comes back injured from a mission.
In this fanfiction, the plot might involve Kushina coming back to help Naruto in his toughest battles. Maybe she uses her unique chakra abilities that Naruto has inherited to give him an edge. She could also provide emotional support, as Naruto has always longed for his mother.
Another theme is growth. Both Naruto and Hinata may have grown separately during Naruto's absence. When he returns, they have to adjust to the new versions of each other. For instance, Hinata might have become stronger in her own way, and Naruto has to recognize that.