One interesting plot could be Naruto seeing how his friends have changed in the future. For example, he might find that Sasuke has become a great leader in the village, and they have a new level of understanding. Another plot could be Naruto learning new and advanced ninja techniques that were developed in the future. He could bring these techniques back to his own time to make Konoha even stronger.
One interesting plot could be Naruto seeing how the village has developed in the future. He might be amazed at the advanced technology and new ninja techniques. For example, he could discover new ways of using chakra that he had never thought of before.
One interesting plot could be Naruto and Naruko traveling back to the time when the Uchiha clan was about to be massacred. They could try to prevent it, which would change the whole future of the ninja world. Maybe they use their future knowledge and skills to stop Itachi from carrying out the order.
One interesting plot could be Minato and Naruto going back in time and Minato getting to see Naruto grow up from the start. He could teach Naruto things he didn't get to in the original timeline, like more advanced jutsu. Another plot might involve them changing key events in the past that had a major impact on the future of the ninja world. For example, preventing certain tragedies or battles.
One interesting plot could be Naruto using his time - travel ability with the Rinnegan to go back and prevent the Uchiha massacre. This would completely change the course of the Naruto world. He could try to reason with Itachi and the elders, and maybe find a way to end the conflict without all that bloodshed.
One interesting plot could be the main character traveling back in time and preventing the initial capture of the bijuus. This would completely change the power dynamics in the Naruto world. Another could be a character using time travel to team up with past jinchuriki to fight a new, greater threat.
One interesting plot could be that they travel back to their childhood days and try to prevent some of the tragedies that happened later. For example, Sasuke might try to stop the Uchiha clan massacre from the start. Another plot could be that they are sent to a time when the ninja world was first being formed and they have to use their modern - day skills to survive and shape the new world.
One interesting plot could be Naruto traveling back in time to his childhood and using his future knowledge to prevent the Uchiha massacre. He could try to change Itachi's path and reconcile the Uchiha with the village.
One interesting plot could be Minato traveling back to prevent the Nine - Tails attack on Konoha. He could use his knowledge of future events to stop Orochimaru from influencing the situation that led to the attack. Another plot might be Minato traveling to a time when the Uchiha clan was on the verge of the coup. With his wisdom and power, he could try to find a peaceful solution and prevent the massacre. Also, he could travel to the time of the First Hokage to learn more about the origin of the ninja world and bring back that knowledge to improve Konoha in his own time.
Well, in some fanfictions, Naruto and Tsunade time travel and end up changing the power dynamics in the ninja world. Maybe they help a small village become a major power by introducing modern ninja concepts. Also, they could time travel to a period when the Akatsuki was first formed and try to disband it before it causes too much chaos.
One interesting plot could be that Naruto and Tsunade travel back in time to the founding of Konoha. They could use their modern - day knowledge and skills to change certain events for the better. For example, Naruto might be able to prevent some of the early conflicts within the village using his understanding of unity. Tsunade could use her medical skills to save lives that were lost in the past, which in turn could have a huge impact on the future of Konoha.