I finally poked around at different Dreamwidth styles. The key incitement was that my old one didn't render lists well in Markdown, insert a line break between a list bullet and the list item. Removing the break from the HTML version wasn't much fun.
Turns out that many modern(?) styles have the same bug. But the Abstractia family does what I want. Then it was a matter of hunting down a variant that wasn't dark on dark, tweaking the colors to have more contrast and also more conventional link colors, and seeing if I could get nice fonts back. Firefox is still a stickler about cross-domain loading, so I couldn't get Elegante to be loaded in it, though Safari did load it. I ended up going with Imperial Script direct from Google Fonts.
Ironically, because I have Firefox impose Garamond everywhere it can, I myself do not get the benefit of seeing my own fancy script. On the upside, I see Facebook and Twitter in Garamond.
I also poked at AO3 work skins today, and got my works to use serif with the least effort possible. Create a work skin containing
#workskin p {
font-family: 'EB Garamond', GaramondNo8, Garamond, Georgia, serif;
}
use the skin for a work, and voila, it'll probably all be in Georgia, unless someone has a Garamond font loaded.