Excellent! I'm positive I saw your plugin while researching the design for my site. It looks like a great package of tools. In the end, I decided to stay away from Rails and use Pelican + Python3. I needed an excuse to brush up on my Python.
Regardless, we've implemented almost identical end-results (I also chose Solarized light, heh) for two different languages' static site generators. All we need is the creator of the Lisp equivalent to chime in...
Edit: Oh, I used Solarized Dark. Thought I swapped that for light at one point, as there's not quite enough contrast across all display qualities.
I put together a project to be able to make new Tufte CSS sites with Jekyll:
https://github.com/jez/tufte-pandoc-css
It makes it easy to use Tufte CSS with markdown (including side notes!)