I think it would be great to have a constant underscore over the baseline, so you can tell single characters apart (a,b,c,d) are currently impossible to distinguish if you have them printed arbitrarily on a page.

Perhaps the characters could be colour coded, too? As we are not limited by having to switch out pens, why not? I think it would make reading much faster and it would be easy to disable/enable.

I dislike the implementation of punctuation, I would prefer a font that uses a monospaced grid and sticks with it, so you can render the font on teeny tiny displays.