I generally write anything that I am motivated to and include lots of nsfw if that suits my fancy. I do this because I like to explore the entirety of human interaction without muting myself. I don't shamelessly plug in nsfw content for the sake of it but if a scene has it, I write it - that's the basics of how I think.

As for what I DON'T write, that can be easily figured out from the "ugh" section of my Condensed Kink List. Other than that, I don't write anything that supports the following:racism, sexism, or anything that promotes hate towards any group without serving a purpose in the story for resolution of an issue.