Taffer v6.0.0 is out. In case you haven't been reading the preview posts: I burned everything down and redrew as 9x9 sets. This improves readability at the expense of a little bit of detail here and there. I think the tilesets have much improved: I really took my time with this and gave everything a good polish. I had to redo the serif font again: the kerning (space between letters) just wasn't working. The new font isn't perfect, but it's the same width and height as the (excellent) sans-serif font, and I've tried to give it some style.
The Damascus font actually came out pretty readable in my opinion. Water, grass, and sand tile beautifully with that set: I wanted to have the big world map be drawn in that tileset, but I figured I'd better stick to the default font. Consider giving it a try.
Hopefully the way I've structured the downloads isn't too confusing. It makes sense to me to split up the dwarf letters and the creature graphics entirely—you had to edit init.txt yourself before and turn the graphics off—but it might confuse people. I've been using 'vanilla' too much and 'canon' doesn't make sense for anything but the default tileset, so I opted for 'orthodox'. And if I have orthodox tilesets, it only makes sense to me (a Crusader Kings 2 player) to have heretic sets (by the emperor...).
Anyways. Enjoy, or be pissed off or indifferent. At least do me a favor though and let me know why you're pissed off or indifferent, so I can improve things going forward.
The 10x10 and 20x20 sets are preserved in Git history. I don't really feel like maintaining them going forward, but I can make them more visible if enough people ask...do give the new tilesets a try though, they really are much more readable.