One idea could be exploring the sisters' lives in modern times. For example, how they would handle social media, modern careers, and different cultural norms. Another idea is to create an alternate universe where the March family has different financial circumstances. Maybe they are wealthy and how that would change their relationships and personalities.
Another common theme is the pursuit of dreams. Just as in the Kdrama, the characters in fanfiction also strive for their goals, whether it's in the field of art, business or relationships. For instance, a fanfiction might detail how one of the sisters overcomes more obstacles on her way to becoming a successful artist. And often, there's a theme of family loyalty. The sisters in the fanfictions usually have a strong bond that makes them stand up for their family no matter what.
The story of Little Women follows the sisters' journey from childhood to adulthood. It shows their different personalities and how they cope with challenges and pursue their own happiness. The book also emphasizes the importance of family, friendship, and moral values.
Little Women isn't a true story. It's a creation of the author's imagination, although it might draw inspiration from some aspects of life at that time.