Not in the Slayers fandom at all (I know who Zelgadis and Lina are, that's it), but I was active in the IY fandom, which is why I was able to nitpick about Sueric so much.

I've read most of Ookami's infamous IYxK fic "Turnabout is Fair Play," but I'm not sure if she ever finished it. And I know Urdchan has "Temple of the Dog," but I never got around to reading it. If you have any other recs, send them my way.