I did some further tests. Fullscreen scaling is set to "low quality" and I tested text done three ways for three fonts.
First its the normal blurry look we get with the Text object.
Second is the same Text with the "alpha clamp" effect with a threshold of 50.
Third is rasterized with the FreeType library without smoothing.
Using alpha clamp looks like it could be usable for some fonts, and you could probably fiddle with the threshold per font. The downside of it is the fonts look more rounded, and thin characters cause gaps.
FreeType has nice results, even with thin parts. The con is it's probably slower, and the js ports aren't in a super usable state.
I ended up using this library and heavily modifying the example to get the results above inside C2, but I wouldn't call it user friendly so I'm not posting it.
github.com/metafloor/freetype-js
Anyways as is it could be handy to make a tool to generate crisper spritefonts from a font.