Gina's fan fiction planning/draft

'American Psycho' by Brett Easton Ellis is one of my favourite books. It has a very distinctive writing style, and a complex and compelling main character. As with many of Easton Ellis's works, much of the story is left to the readers own interpretation. The story is narrated by Patrick Bateman, the central character, who is the 'psycho' and because of this often writes irratically as he himself begins to confuse what is reality and what is not. The text was also made into a movie, but for the purpose of this brief, I will be focusing on the book.

Possible options for Fan fiction

1. A monologue - This appeals to me because of the word limit and also because the internal monologue of a psycho would be interesting to write. The structure and language used would be fluid. However, I am concerned that in the original text, Bateman has many internal monologues, and so I would need to make sure mine explained something different.
2. A conclusion - The text is left open ended and implies that the murders could all be a figment of Batemans imagination. I could offer a conclusion to the story, whether it be that he did kill, or has just lost his mind. I would find this immensely satisfying, however I actually really like how the book ends and would somehow feel like I'm ruining it! But of course with fan fiction it's all about an individuals take on what happened, so really it would just be putting my idea down on paper.
3. Different P.O.V - There are a couple of scenes where Bateman is in a state of high anxiety, or acts very odd amongst friends or colleagues. In particular, the scene where Bateman realises his Buisiness card is not the best has him furious, though he tries to keep an easy manner. It is noticed by his friends but they choose to ignore it. I could possibly make a friend the narrator of the scene, and explore how he feels about the irrational reaction from Bateman.
4. Plot - Bateman is a 'yuppie' - a rich buisiness man who, like his friends, squanders his money on expensive dinners, drinks, face masks, clothes, furniture. He feels like possessions define who you are and how important you are.  By switching his status to that of someone on a much smaller income, it changes his entire viewpoint and way in which he defines himself. Would he still covet the finer things and kill to obtain them, or because of jealousy? Would he kill those less fortunate just to reassure himself that he is still better than some? Would his attitude to women differ? 
5. Time - Could be before or after the novel. It's implied than Bateman has killed before, the novel begins, so perhaps writing about his very first murder. Or even his college years, as they're briefly mentioned in 'American Psycho' and it is obvious he indulged his sadistic tendancies even then. After could encompass his incarceration, or perhaps his continuing killing, or even him settling down.
6. Gender - Batemans crimes are often directed at women, and even those he doesn't kill are subjected to manipulation, verbal abuse and degradation. If Bateman was female, would she have the same attitude, but towards men? Or would she continue to be sadistic towards her own sex? Her style of killing would have to change as well, as she would lack the strength of her male equivalent. 

Well, that's all I've got at the moment. Comments welcome, and opinions on which one I should do would be awesome.

Thanks :)