I disagree regarding light-on-dark vs. dark-on-light, but let's not start that flamewar. Certainly whichever way it works out, it should be consistent. One or two lines of CSS resolves that problem with the classic theme; there's no reason why that CSS shouldn't have been added already. That's a bug in the implementation, but the great thing is that the design is right, so that it can be fixed by CSS.

While I agree that sites should not be broken (white-on-white is broken, no doubts on that!), they shouldn't necessarily be very suitable for internet tablet usage as they stand. (Remaining aware that the topic of this thread is good sites, I'm speaking more generally about all sites.) It would be nice for compassionate webmasters to add CSSs for us, but as our needs are different from "ordinary" browsers, it seems only natural that, until internet tablets become more commonplace, we'll have to make some efforts on our own to get a really comfortable experience.

But if you design content and structure in HTML, and presentation in CSS, it can always be fixed easily for other browsers, either by end-users or by the webmasters.