I just had a revelation (or a short circuit;-) about what to do about the multi-language Main Page.
We set up a new variable (like "{{NUMBEROFARTICLES}}"); say, "{{YOURLANGUAGE}}".
We write that into the first line of the www.wikipedia.org Main Page.
*If* your browser settings have a language other than EN as first preference, this displays a line, saying "There's also a wikipedia in XXX" (of course, in that language!).
If your browser default settings are EN, it doesn't show anything.
So, the US/UK users won't notice a difference, the Germans, French, Spanish, and ... will see a line in their language (maybe with a nice background), guiding the way to "their" wikipedia.
Magnus