Naruto is the central character. In addition, characters who have a connection to Naruto's family history could be main characters. For example, if the fanfic delves into the relationship between the Uzumaki clan and the Senju clan, Tsunade, who is from the Senju clan, could be a main character. And villains who are interested in Naruto's new - found heritage and the power it brings could also be main characters in the story.
The main character is Naruto. But other characters like Jiraiya could be very important. Jiraiya was aware of Naruto's heritage to some extent and could be the one to fully disclose it to Naruto in the fanfic. Also, characters from the Uzumaki clan, if they are still alive in the fanfic's universe, could be main characters. They could help Naruto embrace his heritage and teach him about the clan's traditions.
Well, in many such fanfics, a key plot point could be Naruto finally learning about his Uzumaki heritage which gives him access to unique powers and abilities. Maybe he discovers secrets about his family's past that were hidden from him. Another point could be how he uses this newfound knowledge to gain respect in the village, as the Uzumaki clan was once highly respected.
Well, it could strengthen his bonds. His friends might see him in a new light, with more understanding and respect. For example, they could realize the weight of his past and be more empathetic towards his struggles.
Obviously, Naruto himself is a key character as the story is about him learning his heritage. His mentor, like Kakashi, could also play an important role. Kakashi might notice some strange things about Naruto's abilities and start to suspect that there's more to his heritage. Then he could guide Naruto in the discovery process.
Obviously, Harry Potter himself is a main character. He is the one on the journey of discovering his heritage. There might also be Hermione Granger as she often helps Harry in his adventures and could be crucial in this discovery too.
In the 'naruto heritage revealed fanfic', Naruto will surely be a central figure as the story seems to revolve around his heritage. Besides him, characters like Kakashi might be involved as he has knowledge about Naruto's father. Also, characters from the Uzumaki clan could play important roles as Naruto is from that clan. And of course, Jiraiya, Naruto's mentor, who knew a lot about Naruto's family history and the ninja world in general, might be included to help uncover more about Naruto's heritage.
It's possible he gains enhanced physical abilities like super strength or speed. Since his heritage is often tied to some special genetic traits, these could be unlocked upon the revelation. For example, if his heritage is linked to a powerful clan, he could inherit their natural combat prowess. He could also find out about special chakra control abilities that are exclusive to his bloodline, which would give him an edge in battles.
Kakashi could be involved too. Given that Kakashi has trained Naruto and seen his growth, Naruto might trust him with his secrets. He could reveal his thoughts on how he wants to change the ninja world for the better and the steps he is planning to take in the future.
He might feel angry and frustrated. Naruto has always been proud of his potential and his roots in some way. Being denied his heritage would be like taking away a part of his identity, so he'd likely be quite mad at those who are doing the denying.
In some fanfictions, there could be entirely new characters created just for the purpose of guiding Naruto in his journey to learn about his heritage. These characters could be mysterious hermits or powerful warriors from a forgotten era who hold the keys to unlocking Naruto's true identity.
Well, surely Balto's descendants would be main characters. They carry on his legacy and are likely to be at the center of the story's events.