Old question but must be answered completely. It's very disappointing that it has not been answered in almost a year!
Those images come from either your:
Twitter card image or
Facebook opengraph image
I am not 100% from which one, but I am 100% it is from one of the two, or at least the first image that Google finds while reading your page. So keep this in ...
The list you've outlined looks complete to me, not sure what exactly you're looking for. According to W3, the following elements can go inside the <head>:
<title> (required in every HTML document)
The only thing that's missing from your list that's related to ...
Google dropped support for news_keywords year before last. So now, it neither helps nor hurts SEO, no matter whether your website is a news site or not:
Hi Joost, it looks like we dropped support for this around the time when we removed it from the help center. Keeping it on pages is fine, we just don't use it for Google News anymore. (@JohnMu) February 20, ...
Three and a half months later I have come back to this with an entirely satisfactory solution.
I was unaware of this when I posted the question above in March 2020, but way back in 2011, the W3C included this section in its then-working-draft of HTML5:
Sequential link types
Some documents form part of a sequence of documents. A sequence of documents is one ...