Another way is to explore their family life more deeply. Show how they raise Goten together, deal with daily chores, and still find time for each other. This would add more depth to their relationship as a married couple in the fanfiction.
They could go through a period of misunderstanding. Maybe Gohan makes a decision about his future that Chichi doesn't initially understand. Through communication and some trials, they grow closer as they learn more about each other's perspectives.
They could also develop their relationship through training. If Vegeta takes a more hands - on approach to training Trunks, not just as a student but as his son, they could bond over the shared experience of pushing their limits. They could learn new techniques together and grow closer as a result.
Gohan could be developed by showing more of his academic side in fanfiction. He's smart, and this could be explored further. For example, he could use his intelligence to create new techniques or solve problems that the Z - fighters face. Videl, on the other hand, could be developed by showing her growth as a martial artist outside of just learning from Gohan. She could travel to different dojos and learn from other masters, which would make her an even more formidable fighter in the fanfiction.
One way to develop their characters is to put them in situations that force them to grow. For example, if they were stranded on a hostile planet. Bardock would have to rely on his wits and not just his strength. Fasha could show her nurturing side, taking care of Bardock when he's injured. This would show different aspects of their personalities and help in their character development.
One way is to put them in a difficult situation together. Say they are stranded on an alien planet. Chichi would have to rely on Goten's Saiyan powers to survive and Goten would have to listen to Chichi's wisdom. This would force them to understand each other better and strengthen their bond.
One way is to focus on their shared adventures. For example, when they are on a quest for a new power source or to stop a new threat, they can rely on each other more. Goku can protect Bulma physically, while Bulma can use her intelligence to help Goku strategize. Another way is to explore their past more deeply. Maybe there are some untold stories from when they first met that can strengthen their bond.
A plot could revolve around Chichi wanting Gohan to focus more on his studies and less on training. This causes some tension between them as Gohan feels he needs to train to protect his family. It could show how they resolve this difference in priorities.
They could start by sharing more personal stories. For example, Goku could tell Bulma more about his time on Planet Yardrat. This would deepen their understanding of each other.
One great fanfiction could be about Gohan and Piccolo's training sessions. Gohan, with his Saiyan - human hybrid power, and Piccolo, the Namekian, could be exploring new ways to increase Gohan's power. Maybe they discover a new technique while sparring in the wilderness. This would not only strengthen their bond as mentor - student but also as friends who rely on each other in battles against stronger foes.
One possible fanfiction could be about Bulma helping Gohan with his studies. Since Bulma is super smart, she could tutor Gohan in advanced science and technology. This would not only strengthen their friendship but also give Gohan new knowledge that might come in handy during his battles. For example, understanding the principles of energy and mechanics could help him better strategize against his enemies.
The relationship between Gohan and Chichi also adds depth to Gohan's character. His interactions with his mother shape his personality, making him more than just a powerful fighter. It shows that he values family and the things his mother has taught him, like discipline and the importance of knowledge, which are important positive aspects of their relationship.