I like the idea. You could pick so many odd and unusual dingbat fonts. Something relevant to the book itself even. Then use them as text art, making book art. Not technically ASCII art because of the font, not being monospaced.
Traditional Book Design Using Dingbat Fonts
Making ASCII Art with Fixed Width, Sans-Serif Fonts.
I've been making ASCII art since 1998. I'm a great fan of the FixedSys font. It is a monospace font which works very well for illustrating with text. The individual characters are plain and straight up and down, without many flourishes. (Plain fonts, without flourishes are called sans-serif). FixedSys is also a text which displays on the dark side. This is nice compared to some monospace fonts which give a very light, thin display.
However, Windows Vista was the first new computer I bought where I noticed the FixedSys font is missing. I looked for it, tried other font options, but was not really happy. So I went online to see what people were writing about it.
I now know that FixedSys has been given an upgrade of sorts and is now known as Consolas. I found Consolas and gave it a try. It is nice, smoother than the old FixedSys. But, I am a bit of a traditionalist, loyal to whatever I liked first.
While searching I found the font called FixedSys Excelsior. It is like the old fashioned FixedSys but it is less smooth than the new Consolas font. You can see a pretty drastic difference in the two fonts when I show them in an ASCII art illustration of the Canadian flag.
Monospaced Fonts to Try