Love the work so far. Um, just one note. I have no idea what involves developing a ruleset and what you need to do to piece this together, but one thing wrecking havoc on themes other than the default, is the font colors you've put on the sidebar as well as the color of the sidebar icons. They override existing themes and in the case of the darker ones, they are illegible (the icons, not the fonts; but the latter don't mesh well with some themes). No idea if it's an easy fix or not, but thought I'd mention it.