Idea 1: "Cids Multiple Persona Being Real"
Basically Lord Shadow, Mundane Mann, John Smith and Jack The Ripper being their own character, like Cid, they are character reincarnated and have dreams to be someone they inspired to be, but unlike Cid and becoming Lord Shadow, these characters become the persona originally made by Cid, like the three I just mentioned.
Idea 2: "Eminence In Light"
Basically the very exact opposite of Cid, she would be a female leader named Empress Light and have a group mostly made male characters, they could probably be named by colors instead of something like Alpha, Shadow and Light could be friends or mortal enemies, you can even either make a OC to be Light or use a existing character like Akane or Claire.