Well, they've actually published
modern-day AU high school fanfic of P&P. Not to mention
time-travel self-inserts which hijack the main romance with an OC who is totally not the author's avatar!*
Mere slash is practically staid next to that when it comes to picking from the fandom coffers.
Personally, I'm kind of hoping for professionally published who's-the-daddy mpreg evil twin switch wingfic once they run out of vampire variants. With sex pollen as a motivator.
* I'm not slagging this one. The TV adaptation† was brilliant, what with "I believe this gentleman's name is Mr Tinky Winky", "We'll have twenty children and name them all Amanda!", and giving an entirely new interpretation to "Netherfield".
† ETA: Oops, turns out this has nothing to do with the Austen-inspired
novel of the same name.