Um, my usual answer for details, it depends on the fic. LOL

I saw Seshetta mentioned Clancy. My eyes glaze over.

I guess I personally love when details come out naturally. One thing I dislike is a history and whatever lecture that has little to do with the story. This seems to happen when h/d or any ship visits a museum, aquarium, or the like that the author has been to. A little can go a long way. A lot makes me skim it over.

Go write! Just think of your poor recipient opening up LJ every morning hoping their gift is posted. Yeah, I'm Catholic, too.