"It would be nice to ..." may not fit into that category.
Anyway, as I understand it, on an A4 infographic, you'd be expecting to see one pie chart (H) taking up 3/4 of the page.
Almost all the other 1/4 of the page would be taken up by an He circle.
Then you'd have a (still recognisable as a circle) for Oxygen, at about 6mm wide, the next would be 4mm wide for Carbon.
After that I'd guess we're at ~1mm pie charts for Neon, Iron, Nitrogen.
After the first 7 pie charts, each subsequent pie chart would be the size of a pixel (or sub-mm on a printed page). So it'd look like a hundred or so tiny dots.
Have I misunderstand the visualisation you're describing?
Why do you think the graphic would be printed? If printed, why would it be smaller than 20 feet across? I am confused by these unreasonable assumptions.
In any case, it sounds like you have two things:
a) an interest in having this visualisation, and
b) access to all the tools & data needed to make it.
>where the relative area of each pie chart is dictated by the relative abundance of each element
I suggest reviewing HN's comment guidelines. They're the only reason anyone comes here.
https://news.ycombinator.com/newsguidelines.html