A common plotline is a love - triangle type situation. Giovanni has feelings for Delia, but Delia is in love with Ash's father (in some fanfictions). This creates a lot of drama and tension. Also, there could be a plot where Delia tries to reform Giovanni. She believes there is good in him and tries to convince him to use his power and resources for good in the Pokémon world instead of for the evil deeds of Team Rocket.
Some fanfictions might have a plot where Delia is kidnapped by Giovanni's enemies to get to him. Giovanni then has to rescue her, which makes him realize his true feelings for her. Or perhaps a story where Giovanni and Delia are both on a journey to discover a rare Pokémon species, and during their travels, they start to understand and respect each other more, leading to a deeper relationship.
One popular plotline is the exploration of Silver's relationship with Giovanni as his father. It often delves into Silver's struggle between his own sense of right and wrong and his father's villainous ways. Another plotline could be Silver trying to stop Giovanni's evil plans for the Pokemon world, which creates a lot of action and adventure. And sometimes, there are stories about Silver trying to understand Giovanni's motives and perhaps even redeem him in some way.
One interesting plot idea could be that Delia, Ash's mother, has some long - lost connection to Giovanni. Maybe they were childhood friends before Giovanni took the path of the villain. Another could be a story where Giovanni, for some reason, has to protect Delia from other evil forces in the Pokemon world, which turns into an unexpected alliance. And a third idea might be that Delia discovers a secret about Giovanni's past that makes her question her own understanding of good and evil in the Pokemon universe.
Writers often characterize Giovanni as a complex character. He is still the powerful and somewhat menacing leader of Team Rocket. But in fanfictions with Delia, he may show a softer side. For example, he might be more hesitant to carry out his evil plans when Delia is around. He could also be shown as a bit more vulnerable, especially if he has feelings for Delia and is afraid of rejection or of losing her.
To develop Delia's character, we could show her interacting with Giovanni's world. She could start to understand the motives behind Team Rocket's actions, which changes her view of Giovanni. For Giovanni, we can develop his character by having him experience kindness from Delia. This could make him want to change his ways. Maybe he starts to think about using Team Rocket for good instead of evil. He could also be developed by showing his past traumas that led him to be the villain he is, and how Delia might be able to heal those wounds.
Another plotline could involve their children getting into some trouble during a Pokemon competition. Delia and Johanna have to put aside any differences they might have and work together to help their kids. In the process, they learn more about each other's parenting styles and how they've raised their children to be strong Pokemon trainers. This could also lead to a newfound respect for each other.
Well, a plotline could involve Red trying to redeem Giovanni. Since he is his son, he might feel a sense of obligation to turn his father's life around. Or perhaps Red has to hide his identity from his friends and other trainers, fearing their reactions. He could also be on a quest to find out why Giovanni became evil in the first place, all while dealing with his own Pokemon training journey.
One common theme is the idea of redemption. Giovanni, being a villain in the main Pokémon series, often has a journey towards redemption in these fanfics, especially in relation to Delia. Another theme is the exploration of their different worlds colliding.
One interesting aspect is her motherly role. In fanfiction, we can see how she supports Ash not only with supplies but also with emotional guidance. For example, she might give Ash advice on how to handle difficult Pokemon situations.
Another plotline could be a Pokémon trainer who has a special ability that makes Pokémon more attracted to them. This ability leads to a collection of Pokémon of different species, both male and female, forming a sort of harem around the trainer. They might all compete for the trainer's attention in a friendly way.
Well, perhaps in the fanfiction, Ash is raised by Giovanni in a world where the Pokemon League is more corrupt. Ash might be trained to take over the League for Giovanni's benefit. He could then meet his old friends and have to choose between his loyalty to Giovanni and his true friendships. It would make for a very complex and interesting story.