Everything BUT The Code Editor
I usually use Light Mode everywhere except for what I write code in. Why not? Because I use (Neo)Vim and haven’t found a good light theme for it.
I’ve tested nearly every premade theme I could find, and after a bit of that ended up rolling my own (which I stubbornly used for two weeks before relenting.) They all lack that je ne sais quoi, they never feel perfect to me. And that slight imperfection outweighs the mild discomfort I get from themes with light text on dark backgrounds.
And it’s really not that bad coding in a dark theme. The bright colors really help with readability on dark backgrounds, and you don’t get that on plaintext. I think a significant problem with light code themes is the bright syntax highlighting on the bright background. I’m no theme design expert, but that’s what I’d pin it down to.
The Solarized themes did a great job at literally making me tired, somehow. I didn’t think colors could have that effect, really.