I don't care about het/slash/gen, anything is fine. If I specified a pairing it's a preference, not a necessity. I prefer no outright rape, though dub-con and rape fantasies are fine. I enjoy angst as long as nobody dies and the story ends on a happy - or at least upbeat and hopeful - note. I really don't handle depressing stories well, and I don't like to read deathfics at all.
I'd rather have a story with a bit of plot and lots of interesting character interaction than one that is all about the smut. Plot, character interaction and smut are of course awesome together. I love stories that show the deeper side of a character; why they are the way they are, and what parts of them are hidden from other people. I'm not fond of outright crack, though humour is fine as a part of the story and not the whole.
I hope this helps, and I'm sure that I will love whatever you write no matter what it is. I didn't give really specific requests because I really will be happy with anything at all! Anything that moves you and that you think is interesting is probably going to thrill me. Happy writing, and merry Yuletide!