He could develop the ability to combine his chakra with Superman's powers. For example, he might be able to use his Rasengan while flying at super - speed. Or he could infuse his chakra into his heat vision to make it even more powerful.
Lois Lane is a must - include. She can be the love interest and also a strong - willed journalist. Jimmy Olsen is also great, providing some comical relief and being Superman's friend. Lex Luthor is an obvious choice as the main villain, always plotting against Superman.
One idea could be having Superman face an enemy that can manipulate time, causing chaos in Metropolis. Another could be a story where he has to deal with a powerful alien artifact that is affecting his powers. Maybe also a plot where he teams up with a new superhero from another planet.
Superman, of course, is the most important. Then there's Lois Lane, the journalist who is always on the hunt for a story and has a special relationship with Superman. Lex Luthor is also crucial as the main antagonist.
In the 'The Adventures of Superman Novel', a significant plotline is Superman's origin story. How he came from Krypton and was raised on Earth. His discovery of his powers and how he decides to use them for the greater good. Also, his relationships with Lois Lane and other characters in Metropolis play a big part in the plotlines as he tries to balance his personal life with his superhero duties.
Obviously, Superman himself is the most important. He is the hero with superpowers. And Lois Lane is also important as she is often in the middle of the stories and has a relationship with Superman.
One main theme could be heroism. Superman is always saving the day, which shows the importance of having heroes. Another might be justice as he fights against evil to bring fairness.
Well, in fanfiction, Naruto's chakra - based powers like the Rasengan could be combined with Superman's super strength. For example, Naruto could use his chakra control to enhance Superman's punches, making them even more powerful. Or Superman's heat vision could be mixed with Naruto's fire - style jutsu to create a more intense and unique attack.
In a Naruto - Superman powers fanfic, perhaps Naruto gets some of Superman's powers accidentally. He struggles to control the new powers like heat vision and super speed along with his own ninja abilities. Superman, on the other hand, discovers he can use chakra in a limited way and they both have to figure out how to use these new combinations of powers effectively.
If Batman had Superman powers in fanfiction, he would be an unstoppable force. He could use his detective skills combined with super strength, flight, and heat vision. Gotham would be a much safer place as he could quickly stop crimes across the city without relying on his gadgets as much. He might even be able to take on more global threats, which would be a huge change from his normal focus on Gotham's underworld.