Gaara could be one of the characters. He has a bond with Naruto and if Naruto is against Konoha, Gaara might get involved to help Naruto or at least try to mediate. Shikamaru is another likely character. His intelligence would make him a key figure in trying to understand Naruto's motives and also in devising strategies for Konoha. Hinata might be involved as well, because of her feelings for Naruto. She might try to protect Naruto from Konoha's attacks.
Sasuke would likely be involved. He has his own issues with Konoha and might side with Naruto, either out of friendship or his own vendetta against the village. Also, the elders of Konoha like Danzo could be important characters as they might be the ones behind Naruto's banishment.
Sasuke could be involved. He might either try to stop Naruto from leaving, believing that they should face whatever comes together in Konoha, or he could decide to join Naruto on his journey, as they have a deep bond.
Sasuke is often a common character. He might have a different reaction to Naruto's banishment compared to the original story. Maybe he decides to join Naruto outside of Konoha or tries to find a way to get him back. Kakashi could also be there. He might be conflicted about Naruto's banishment and could play a role in either helping Naruto secretly or trying to uphold Konoha's decision.
Jiraiya could be another one. Since he was Naruto's mentor, he might go after Naruto when he's kicked out and continue to train him in secret.
Sasuke could be involved. Since they have a complex relationship, Sasuke might either be a rival during Naruto's training, pushing him to be better, or he could end up joining Naruto in some training sessions to become stronger together.
Sasuke is an obvious choice. He has a connection to Naruto that goes beyond just friendship or rivalry. He might be the one who first discovers Naruto's predicament and sets out to find a solution. Sakura is essential too. Her skills as a medical ninja are crucial. She could be the one who patches Naruto up every time he gets injured in his fight against whatever is threatening his life. Also, characters like Jiraiya might make an appearance. Even though he's dead in the original story, in this fanfiction, he could come back as a spirit guide to help Naruto find a way to 'refuse to die', giving him advice based on his own knowledge and experiences.
Sasuke is likely to be involved. He and Naruto have a complex relationship and Sasuke has become an ally. He could offer his strength in combat to protect the rebuilding efforts. Also, Sakura. She's a skilled ninja with medical abilities that could be useful if there are any injuries during the process.
There might be characters from Iwa who oppose Naruto. For example, the Tsuchikage of Iwa would surely be involved as the leader of the village Naruto is attacking.
Sasuke is likely to be involved. Given their complex relationship, Sasuke might be on the receiving end of Naruto's rage at times or be someone who tries to understand and calm him. Kakashi could also be there, as Naruto's sensei, he would surely be involved in dealing with Naruto's rage.
Sakura could be one of the main characters. She has a long - standing relationship with Naruto and might play a role in convincing him to return. Maybe she tells him about the state of the village's hospital or how his friends miss him.