Fanfic reading patterns

I've been thinking lately about preferences in fanfic reading.  Most of my favorite genres and tropes of fic remain the same across fandoms, but there are some types of fic I seek out strongly in one fandom but rarely in other fandoms.

( under a cut because of being rambly and somewhat navel-gazing )

What about you, friends?  Are there any interesting patterns in what sorts of fanfic you enjoy in different fandoms or at different times in your life?