Well, Hisoka's origin story in Hunter x Hunter is quite interesting. He hails from Meteor City, a place that's more like a dumping ground for the unwanted. Growing up there, he was exposed to all sorts of things that normal people wouldn't experience. His love for fighting strong opponents probably stems from the fact that in Meteor City, strength was the only way to get what you want. Hisoka's nen abilities are also a product of his environment. He's constantly evolving and seeking new challenges, which is likely a trait he developed while growing up in a place where only the fittest survive.
There's a fanfic called 'Hisoka's Obsession with Machi'. It delves into Hisoka's perspective. He is constantly intrigued by Machi's skills and her cold exterior. The story has some interesting scenes where Hisoka tries to get closer to Machi, and Machi is both repelled and fascinated by him at the same time. It's a really engaging read.
I also like 'Kurapika and Kuroro: A Shared Quest'. It's a story where they both embark on a journey to find a powerful and mysterious item in the Hunter x Hunter universe. Along the way, they face many challenges and their interactions are full of tension and some unexpected moments of camaraderie.
Characterization is key. A great Kurapika fanfiction really nails his complex personality. His loyalty, his anger towards the Phantom Troupe, and his internal struggles should all be well - presented. For example, if it's a story about Kurapika during his revenge journey, it should show how his emotions are constantly in flux.
If we consider a gender - swapped Kurapika in a fanfic, it could have a significant impact on the story arc. For example, if Kurapika was female, her emotional journey might be perceived differently. Her anger and determination for revenge could be seen as more of an underdog story, as in some fictional universes, female characters are often underestimated. This could add more depth to her character as she overcomes these biases.
A prevalent theme is the struggle between good and evil. Kurapika is often seen as a symbol of good, while Chrollo represents evil. Fanfictions play around with this dynamic, sometimes blurring the lines between the two. Also, the theme of trust is common. Given their history, it's interesting to see how fanfiction authors make them build trust in each other, like in a story where they have to rely on each other's skills to survive a dangerous situation which spans over a long journey.
One great fanfic is 'The Unlikely Bond'. It delves into the complex relationship between Hisoka and Gon. The author beautifully captures Hisoka's twisted fascination with Gon and Gon's naivete in dealing with it. It has some really interesting plot twists that keep you hooked.
I really like 'Hisoka's Obsession'. It shows Hisoka's fixation on Gon in a more detailed and somewhat darker way. It adds layers to Hisoka's character while also developing Gon's reactions to Hisoka's strange behavior. The writing style is engaging and it's easy to get lost in this alternative take on their relationship.
One popular Hisoka fanfiction might be those that explore his backstory. Since in the original 'Hunter x Hunter' his past is quite mysterious, fanfictions often fill in the gaps. For example, there could be stories about his early days as a Hunter and how he developed his unique nen abilities.
A good fanfic in this regard often has well - developed characters. Since Kuroro and Kurapika are both complex, their motives, backstories, and personalities should be explored in depth. For example, Kurapika's quest for revenge against the Phantom Troupe and Kuroro's leadership of the troupe are key aspects.