To develop Samus, make her more vulnerable in the fanfiction. Let her show emotions other than her typical stoic self. For example, she could be frustrated with some of the wacky situations they get into with AVGN. As for AVGN, develop his backstory. Maybe he had a difficult childhood related to games that made him so critical. As the story progresses, he starts to let go of some of that negativity and becomes a more positive force in their adventures.
Perhaps in the fanfiction, Samus is on a mission to retrieve a powerful and corrupted video game cartridge. This cartridge is causing glitches in the entire gaming universe. AVGN, being the self - proclaimed video game expert, joins her. Along the way, they have humorous exchanges as Samus tries to understand AVGN's strange references to retro games and bad game design.
A good way to develop their relationship is by showing how they grow together. Maybe Samus teaches Baby Metroid some things about the universe, like how to recognize different types of energy or how to avoid certain traps. And Baby Metroid could teach Samus about the Metroid way of life, such as how they sense their surroundings. This exchange of knowledge and experiences would create a deep and unique relationship between them.
Another method is to organize fanfiction contests. Set themes that are positive and in line with the spirit of the Metroid franchise, such as Samus' heroism or her exploration of the universe. Offer prizes to the best entries to motivate more people to create positive fanfictions.
For Naruto, you can focus on his growth in a different aspect. Since he already has his ninja skills, in a story with Aplessia, he could develop his emotional intelligence further. For example, learning how to better understand Aplessia's more complex and perhaps different emotional range compared to his friends in Konoha. For Aplessia, you can start by giving her a backstory. Maybe she has a troubled past that made her the way she is, and as she interacts with Naruto, she starts to open up and become more confident.
In fanfiction, Naruto could be developed by having him face new moral dilemmas when interacting with Yubel. His character could grow by learning about different forms of power that Yubel represents.
For the mother character, you can show her growth from shock at the news to determination to bring all the babies into the world safely. She could start as a timid person but become strong and assertive. The father could be developed by showing his support system for the mother, like taking on extra jobs to afford the upcoming expenses. He might also have his own fears but hides them to be strong for his family.
In fanfiction, Goku's character can be developed by exploring his family side more in relation to Sakura. Maybe he sees her as a sister - like figure and tries to protect her. This would show a different side of his protective nature. Sakura, on the other hand, could be developed by her learning about Goku's simple yet determined mindset. She could then apply some of that to her own life, like being more straightforward in her goals. This would change her character in a way that makes her more confident and less self - doubting.
For Harry, you can explore his growth in a non - magical world. He might initially struggle without his wand and the familiar magical environment. But as he teams up with Batgirl, he could learn to adapt and use his wits and basic magical knowledge in new ways. For example, he could use his knowledge of potions to create makeshift antidotes for toxins in Gotham. Batgirl, on the other hand, could learn about the existence of magic from Harry, which could expand her view of the world. This new knowledge could make her more open - minded when facing unusual threats in the future.
Develop other inmates as well. For instance, create an inmate who has a tough exterior but a soft heart. Sakura could be the one to break through that tough exterior. You can also show how different inmates have different reasons for being in prison and how those reasons shape their personalities. Some might be remorseful, while others might be defiant. By having Sakura interact with these different characters, it can enhance the overall character development in the fanfiction.
Characters can be developed based on their relationship with the advanced technology. For example, a character could be a tech - phobic in a world full of advanced gadgets. His struggle to adapt would show his personality traits like stubbornness or fear of change.