Okay I’ll poison the well in a reply to the poll. Light theme by default all the way, easily.
Light theme is what the majority of websites use, including Wikipedia, which is familiar to users, and is why we use the wiki skin that we do.
Nobody has ever been offended or put off by a website using a light theme. The same thing cannot be said for dark theme. We’re trying to reach out to newcomers and get them interested, not put them off with a cultish colour scheme.
There are arguments about eye strain and this and that, but that’s solveable with a toggle button. The average newcomer to EM for the first time hasn’t the slightest clue about eye strain in relation to different colour schemes, they just get a quick initial opinion about the site, choose to read more or close it and never see it again. First impressions are damn important, that’s why I firmly believe light theme is the way to go, as I literally see enabling dark theme by default as putting off like 50% of people who view the wiki, massive turnoff for most people.
But hey, we do things by consensus here. Will hopefully have an easy toggle for all readers built in at some point.