She can be developed by giving her a backstory. Maybe she had a difficult childhood that made her so self - centered. This would make readers understand her actions better. For instance, if she was bullied as a child and now uses her popularity as a shield.
One idea could be Scarlet Lady actually learning to be a better hero over time. Maybe she starts to see the error of her ways and tries to make amends with Ladybug and Chat Noir. For example, she could start training harder to improve her skills instead of relying on her looks all the time.
A new villain could have a weapon that specifically targets Ladybug's powers. When she tries to use her yo - yo or her powers of creation, it backfires and causes her harm. This would force her to rely on her wits and Chat Noir more than ever. They would need to find a way to neutralize the weapon and heal Ladybug.
In a fanfiction, Ladybug could get hurt as a result of a trap set by Hawkmoth. He might have studied her fighting patterns and set up a situation where she is lured into a place full of obstacles that cause her physical harm. This would not only test her physical strength but also her mental resilience as she tries to figure out how to escape and continue her fight against evil.
There are indeed. Fanfiction writers often come up with creative stories involving the wolf miraculous in the Miraculous Ladybug world. They might explore how a new holder of the wolf miraculous interacts with Ladybug and Chat Noir. It could be about a character who discovers the power of the wolf miraculous and has to learn how to use it to fight against Hawk Moth's akumas. You can also check fanfiction.net for some interesting reads.
It could be Gabriel Agreste. He has been a suspect in the original series for various reasons. He is often absent and has a lot of secrets. So in the fanfiction, it would make sense if he was finally revealed as Hawk Moth.
In a Miraculous Ladybug sleepover fanfiction, the characters might have a lot of fun. They could play games like truth or dare, which could lead to some interesting revelations. For example, Marinette might accidentally let slip some of her feelings for Adrien.
Common themes include identity. The character with the wolf miraculous often has to keep their identity a secret, just like Ladybug and Chat Noir. Also, there's the theme of discovery. The discovery of the wolf miraculous, its powers, and how it fits into the overall Miraculous Ladybug lore. There are also fanfictions that focus on the relationship between the wolf miraculous holder and other characters in the show, whether it's a friendship or a rivalry.