[aciccarello]I tried not to over complicate things. I didn't bother with Dublin core. I don't even know how you'd figure out JSON-LD with all the ways it can be used. I included OGP, Twitter cards, and some basic meta tag fallbacks.
[aciccarello]I wish I had some better statistics on usage though. I'd consider dropping Twitter cards given most sites also include OGP if they have Twitter cards.
[tantek]indeed I wouldn't bother with JSON-LD data islands because the only big consumer is Google Search which means they are dominated by SEO spam. it's more likely to be noise than signal