Which is why this subforum is 93% gibberish.
I played some more, tried Titillium Web as the font (this is the one used across most of the Factorio gui). Made the text "frames" vanish when there is text (and return when there is no text), with the idea that they can be re-highlighted on mouse-over/alt-mode or when the plate gui is opened so you can still see what space you're working with.
But the kerning issue turns out to actually be a major one - look at the way W and A next to each looks like total shit. You can't just have a fixed spacing between letters regardless, because letters with sloping/curved sides need adjustments. Every proportional font does this. So I think this is where I drop the idea because I'm not dicking around with trying to extract kerning table info from a TTF. Some fonts have thousands of entries in the table, covering every possible character combo. All of that would be done automatically by just rendering the vector font but I've got no interest in that.