Well, one of the main plot points is the emergence of new Death Notes and new users. There are different individuals who get their hands on the Death Notes and start using them in various ways, which leads to a complex web of power struggles and moral dilemmas.
It focuses on the story of L's early days and how he solves cases. In this novel, we see L's unique detective methods and his battle of wits against various criminals.
The theme of sacrifice also exists. L is aware of the risks he takes in dealing with the power of the Death Note and is willing to sacrifice his own safety for the greater good. And there's the exploration of human nature when faced with such a powerful and dangerous tool as the Death Note.
Obviously, L is a very important character. He is a super - intelligent detective with unique quirks. His deductive skills are second to none, and he is constantly on the hunt for the truth regarding the Death Note. Then there's Near, another highly intelligent individual who is also involved in the events related to the Death Note.
One possible fanfiction could be where Light is in the hospital due to an unexpected illness. Maybe he uses this time to plot his next moves in the Death Note world without arousing too much suspicion. He could be pretending to be weaker than he actually is while observing the people around him, looking for potential Kira supporters or enemies among the hospital staff and patients.