I like "content" vs. "warnings." That's what I use in my headers, for the reasons you specified above (unless a fest - like the holiday swap - requires me to use "warnings"). It just seems like the most accurate label while still being neutral. The thing that got that ball rolling for me was seeing people warning for slash or boys kissing or whatever. (I admit, when I first started writing slash several years ago, I did this. I was in a tiny het-centric fandom and I felt like I was going out on a limb. Obviously that's not something I'd warn for anymore.) I get that slash is not everyone's thing, but warning for it makes it sound like a perverted act that people should read in secret and never admit to, and so does warning for kinks. It's nice to let people know that it's in there, but mostly so they can know whether or not it's something they want to read. I know a lot of people use "warnings/enticements" which at least implies that one person's warning is another person's enticement. I know if someone warned for watersports or face-fucking or bestiality, I'd definitely consider that an enticement more than a warning!

I also sometimes find warnings hilariously unnecessary. Like warning for incest when the fic is clearly labeled Chin/Kono and it's rated NC-17 and the summary says, "Chin and Kono fuck on his bike." Really, there's going to be incest in that??? Shocker! Same with things like age discrepancy when it's obvious that there's going to be an age discrepancy between Harry Potter and Scorpius Malfoy, given that Harry is the same age as Scorpius's father in canon.

I need to finish that Steve/Danny watersports fic for you! I think I had about 800 words...