What, you don't like Touka? I thought it was an entertaining one... Touka does not take no for an answer.
Wahaha is great, yeah. Funny character.
That pretty much sums up that one, yeah.
That episode might be the least yuri special, but might be the cutest...
That one might be the best of the specials... (more below too)
Yeah, it's a great series. What do you mean, if you know what you're getting into, though? You don't need to know everything about the series at the start to like it.
Huh? Weird lighting? No, it is the quite skimpy dress that it appears to be.
Agreed on both points.
Covering? Actually, the dress itself (which is, of course, quite short too) doesn't cover her breasts at all; instead, it Vs below them, and goes around them on the sides. The breasts are only covered with that scarflike shirt tied in the center.
The two pieces may be attached underneath -- it looks like it's only got one shoulder strap per side, after all -- but it's clear that that'd be on the sides, so from the front at least what I described is how that dress has to work.
Unless you can't see the difference between her skin color and the dress, how would being colorblind affect anything? If that is the case though, it's as I described above, basically an under-dress and over-scarf/shirt thing, with a large window of sorts in the center.
How does it not fit her character? You're right that she doesn't wear anything else quite as revealing, but consider that early in the first season Nodoka was completely fine with that maid uniform while Saki was embarrassed, and that she wears frilly stuff all the time (even if she complains about the term) in both Saki and her younger appearance in Achiga-hen. And that costume there certainly fits the frillyness aspect. Also consider her Nodocchi alter-ego's costume, which backs up all of those points.
As for the scantiness... well, it's summer, and so she's dressing down. People clearly are much less bothered by such things in the Sakiverse versus reality; also note those ridiculously scant summer costumes of Hajime's that make Nodoka's there look quite conservative... and nobody says a word about it, at least not from a "that exposes too much" standpoint.
So considering all of the above, Nodoka is the serious character who does not believe in superpowers or magic and blushes easily (when around Saki), but also likes dressing like how she does in the series when not in her school uniform. I don't think there's a conflict there really.