Sure. 'A Court of Thorns and Roses' has a similar allure with its complex characters and richly built fantasy world. It also features a strong romantic sub - plot like 'Neon Gods Novel'.
Yes, there often are. In some Sword Art Online fanfictions, gods can be introduced as powerful entities. They might have unique abilities and play important roles in the story, such as influencing the game world or the characters' fates.
Well, in kurapika and neon fanfiction, a common theme could be the contrast in their worlds. Kurapika is from a tragic background with his clan's destruction driving him. Neon, on the other hand, is a part of a wealthy and powerful family. Fanfic writers may play with the idea of how these two from such different walks of life come to understand each other. Maybe Kurapika sees in Neon a glimmer of innocence that he wants to protect, or Neon could be intrigued by Kurapika's mystery and strength.