512kb is huge :-)
Still, made me look at my home page again. About 77kb, of which 51kb is fonts. I think you can go down a rabbit hole with this when the basics are already there, but system fonts, webp images etc. etc.
It really is. I'm already using system fonts / webp (where the browser supports it) and so forth. Further reduction (beyond tracking down those gravatar images) would require me to breakapart my js bundle, which doesn't quite seem worth it.