One possible storyline could be Naruto spending Christmas alone in his small apartment in Konoha. He reflects on his past, how he was always alone as a child during the holidays. He might see all the happy families and friends celebrating together in the village, which makes him feel a bit sad but also more determined to create a family of his own someday.
Perhaps Naruto gets a mission on Christmas Eve that takes him to a far - off place. There, he encounters a group of orphans who are also alone during Christmas. Naruto, remembering his own lonely childhood, decides to stay and celebrate with them, sharing stories of his ninja adventures and bringing some joy to their otherwise gloomy Christmas.
In this fanfiction, it could be set in a time when Gohan is off at university and Videl is still in their hometown. They both feel lonely in their different situations. Videl misses Gohan's presence, and Gohan feels out of place among regular humans at university. They communicate through letters or occasional phone calls, and their longing for each other grows. When Gohan finally comes back for a visit, they realize how much they mean to each other and start a relationship that is based on their shared experiences and the loneliness they've endured apart.
One possible storyline could be how the Hidden Leaf Village copes with his death. Maybe there are power struggles as different clans vie for leadership in the absence of Naruto's unifying presence.
One possible storyline could be that Kalawarner somehow ends up in the Naruto universe. She might be confused at first but then use her own skills to help Naruto and his friends in a battle. Maybe she has some unique powers that are useful against a new enemy.
A storyline could involve Naruto using his newfound Nara abilities to solve a mystery in the village. Maybe there's a strange phenomenon that's related to shadow - based jutsu, and Naruto, with his understanding of both Uzumaki and Nara powers, is the only one who can figure it out. He'd have to team up with other characters, and in the process, there would be a lot of character development and interesting interactions.
Another storyline might be that Millet is a secret organization in the Naruto world. Naruto discovers that this organization has been pulling the strings behind some of the conflicts. He has to infiltrate it and expose their true motives. This would be a great opportunity for Naruto to use his stealth and combat skills, as well as his ability to make friends and allies within the organization to bring it down from the inside.
One possible storyline could be that Naruto is chosen as a temporary Kazekage due to a threat that requires his unique skills. He then has to deal with internal conflicts within the Sand village while also facing external enemies. Another could be that there is some kind of prophecy that only Naruto can fulfill as Kazekage to save both Konoha and Suna.
One possible storyline could be Naruto as an elf trying to fit into the ninja world while still having his elf heritage. He might face discrimination from some who don't understand his different nature.
In a Naruto and Derieri fanfiction, a possible storyline could be that Derieri is mistaken for an enemy in the Naruto universe. Naruto, being the one to see her potential for good, tries to convince others that she is not a threat. As they try to clear her name, they uncover a conspiracy that threatens both their worlds. This would involve a lot of mystery - solving and action as they race against time to stop the conspiracy.
In a Naruto fanfiction, Jaune Arc could start his own ninja clan. He could use his knowledge from RWBY to create a new style of combat that combines aura and chakra. Maybe he falls in love with a kunoichi and has to deal with the cultural differences between his world and the Naruto world while also facing off against powerful villains who want to steal his new - found ninja techniques.
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.