One common theme is Charlotte's growth as a character. In many fan fictions, she overcomes various challenges that help her become stronger and more confident in herself.
One great piece of Infinite Stratos Charlotte fan fiction is 'Charlotte's New Adventure'. It shows Charlotte in a whole new situation where she has to face a new type of enemy in the IS world. The story really delves into her character, highlighting her intelligence and determination.
The Infinite Stratos manga doesn't always go past the anime. It could be on par or have a different focus. Usually, it's up to how the story is envisioned for each medium.
One major difference is the pacing. In the anime, the story moves at a faster pace to fit within the episode limits. For example, some character developments that are more detailed in the novel are rushed in the anime. Also, the visual representation in the anime may not always capture all the nuances described in the novel. The anime might simplify some complex plot points for easier viewing.
Infinite Stratos 'novel was not finished yet. This was a famous web novel that described the experience of the protagonist, Ye Fan, in the infinite style. The story unfolded from Ye Fan's perspective. After experiencing a series of adventures, he became one of the strongest existences in the infinite style. However, the story was not over yet. The author, Er Gen, was still working on the story, and there was no news of the end yet.
For me, the novel is better in terms of story - telling. It has more room to develop the plot and characters gradually. The anime often has to cut corners to fit into a set number of episodes.
In a fanfiction, Ichika and Houki could have a moment where they confess their feelings for each other. Maybe it starts with a simple misunderstanding. Houki sees Ichika with another girl and gets jealous. But then Ichika clarifies that he only has eyes for Houki, leading to a very sweet and heartwarming confession scene.