One plot idea could be that the vampire girlfriend is initially hiding her true nature from Naruto. She might be drawn to his positive energy and strong will. As the story progresses, Naruto discovers her secret during a battle when she uses her vampire abilities to save him. Another idea is that she is from a clan of vampire ninjas and Naruto has to help her reconcile with her clan while also dealing with the ninja world's reaction to vampires.
A possible plot could be that the vampire girlfriend was created by an evil jutsu gone wrong. Naruto meets her when she is lost and confused. He takes her under his wing. But as she struggles with her new - found vampiric urges, Naruto has to teach her self - control. Meanwhile, they have to deal with the shinobi who are out to destroy any unnatural creatures like her.
One plot idea could be that the vampire girlfriend is from a noble vampire family, and her family opposes her relationship with a human. So they have to fight against her family's wishes. Another idea is that the vampire girlfriend has lost her memory of being a vampire, and the human boyfriend has to help her discover her true nature while protecting her from other vampires who might take advantage of her.
One plot idea could be that Naruto discovers the Keyblade while on a strange new mission outside of the Hidden Leaf. He initially has no idea how to use it but through trial and error, he starts to unlock its powers. Another idea is that the Keyblade is a gift from a mysterious sage who believes Naruto has the potential to use it to save both the Naruto world and the world connected to the Keyblade. Maybe Naruto has to use the Keyblade to fight against an enemy that can manipulate time and space, which is a new and dangerous threat to his village and friends.
Another plot could be that the Sharingan is given to Naruto as a last - ditch effort to save the village. A dying Uchiha gives Naruto his Sharingan, and Naruto has to figure out how to incorporate it into his already powerful set of skills. He might have to deal with the jealousy or suspicion of some of his comrades who are wary of the Sharingan's power.
A third plot idea is that Naruto is given the Rinnegan as a last resort to save the ninja world. An old sage or some kind of divine being bestows it upon him. But with the Rinnegan comes a prophecy that he will either save or destroy the world. Naruto then has to battle his inner demons as well as external foes, all while trying to understand the true nature of the Rinnegan and its place in his destiny.
One plot idea could be Naruto constantly falling asleep during important ninja missions. His friends initially think he's being lazy or irresponsible, but then they discover it's a medical condition. They start to adapt their strategies to protect him when he's asleep and also find ways to manage his narcolepsy so he can still contribute to the team.
Perhaps Naruto is on a mission in a strange new land where guns are the common weapon. He gets his hands on a couple of guns and has to quickly learn how to use them to survive. His chakra abilities combined with the guns' power make him a unique and formidable fighter in that land. His friends back in the village are initially skeptical when they hear about it, but then they see how effective he can be.
One plot idea could be that Vampire Naruto has to protect Kurenai from other vampires who see her as a threat. Since Naruto has unique powers as a vampire, he can use his speed and strength to fend them off.
Well, a possible plot is that Anko's vampire nature gives her unique abilities that Naruto finds useful in a mission. They could go on a journey together to find a cure for her vampirism because Anko wants to be fully human again. Along the way, they face various challenges and their relationship grows from distrust to friendship.
A possible plot is that the baby's existence causes a stir in the ninja world. Some may see it as a symbol of unity between the Uchiha and Uzumaki clans, while others might fear its power. Naruto and Sasuke then have to deal with political intrigue as they try to raise their child in a peaceful environment. Also, the baby could inherit Naruto's positive attitude and Sasuke's intelligence, which could lead to some really cute and interesting interactions within the family.
One plot idea could be that Naruto discovers his golden chakra has a special connection to an ancient prophecy. This could lead him on a journey to find out more about his power and how it relates to the future of the ninja world. Maybe he has to unlock different levels of the golden chakra to face new and powerful enemies.