In some 'naruto is a father fanfiction', there could be a story where Naruto's child has a unique power that no one in the village has seen before. Naruto, as a father, has to protect the child from those who might fear or want to use this power for their own gain.
In some 'naruto is a father crossover fanfiction', there could be a storyline where Naruto is a father in a crossover with the Harry Potter world. His child could be a student at Hogwarts, and Naruto, with his experience of being a hero, tries to understand the magic world and protect his child from the dark forces. Maybe he uses his chakra in unique ways within the magical environment.
One interesting storyline could be a young father Naruto trying to balance his ninja duties with raising his child. He might have to take his baby on missions, which would lead to some comical and heart - warming moments as he tries to protect the baby while fighting enemies.
One possible storyline could be Naruto struggling to balance his ninja duties with raising his child alone. Maybe he has to take the kid on missions sometimes, teaching the little one about the ninja world along the way. Another could be Naruto dealing with the judgment of the village as a single father, showing how he overcomes that and still raises a strong and kind - hearted child.
One possible storyline could be that Naruto's child in the fanfiction inherits some of his unique powers, like the Nine - Tails' chakra. And they have to learn to control it, with Naruto guiding them. Another could be that the child gets into trouble in the ninja world and Naruto has to use his influence and skills to protect them.
Another storyline might focus on the relationships between the Sand ninja and the Leaf ninja. For example, how they overcome their past differences and work together on a mission. It could involve a lot of character development and understanding between different cultures in the Naruto universe.
One interesting storyline could be a crossover where Naruto somehow ends up in Hippolyta's world. He might use his ninja skills to help the Amazons in their battles, like using his shadow clone jutsu to create distractions during an enemy attack.
Another storyline might involve Koharu being in danger and Naruto coming to her rescue. In the process, they discover a hidden bond between them that was previously unnoticed. Maybe they find out that they are related in some long - lost way or they just develop a deep friendship that changes the way the village views their relationship.
One interesting storyline could be exploring the backstories of minor characters in the Naruto universe. For example, how a random villager in Konoha came to be there and their family history.
One interesting storyline could be where Naruto and Izumi meet during a mission outside of Konoha. They initially have some misunderstandings due to their different upbringings, but as they work together, they start to understand each other better. Another could be a story set in an alternate universe where Naruto is not from Konoha and Izumi is sent to find him. They end up on a journey together, facing various challenges and growing closer along the way. A third one might be a time - travel story where Izumi goes back in time and meets a younger Naruto, and she tries to change the future for the better by influencing him early on.
Some fanfictions focus on Naruto having a different upbringing. For instance, if he was raised by a different clan, like the Hyuga. This would give him access to their unique abilities and fighting styles. He could also have a different set of friends and rivals, which would completely reshape his character development and the overall plot of the story.