I have read the Swedish design company 1910's blog post before trying this Userstyles script, and so far, I like it.
I think the legibility of Wikipedia (and other Wikimedia sites) actually depends on how a MediaWiki skin is designed. So, why don't you let the team at 1910 to design a MediaWiki skin (with some tweaks from their original suggestion), and let the users at all the Wikimedia sites to try it?