Hi Abraham,
great that it has come to that point, congratulations.
At a time we'll surely try out the effect on our new _big_ Oskar Fried score :-)
I'm at least very interested how it will come out with Cadence, but for a dense orchestral score it may also be interesting to use Haydn (I liked the Bach examples very much).
A few (minor) comments:
The new overview comparison is very useful indeed. But I'd suggest starting this with an image of LilyPond's default output (with a link to the full-size image, but no detail page).
I think it would be a good idea to replace the full-size PNG files with PDFs. You want people to be interested in detail, don't you? Then PDFs would allow them to look really close.
In the patch installation you could (re-) add a note about making a backup of font.scm.
As for the font installation I think you should add a small note that the patch and/or font installation is only valid for exactly that installation, and that one has to repeat it for any new installation (I don't know what a Linux package manager would do with the extra fonts - maybe they would be left untouched).
I have written a script that will "install" the fonts using symbolic links. Instead of copying the font files in each parallel LilyPond installation (and I have many) they are stored in one place and linked into the respective font directories. It is a preliminary version which only works with downloaded installations on Linux and custom builds so far. Support for Mac should be trivial, for Linux package manager versions too. AFAICS it's not (easily) possible to support Windows (but I'd be happy about suggestions).
You can find it here
https://github.com/openlilylib/openlilylib/tree/master/fonts.
Maybe you'd like to improve it and make it somewhat more robust. You could then add a link to it on your page.
I would very much favor including the style sheets in openlilylib.
That's all for now. Keep up the work :-)
Best
Urs