Love it.
I agree that a progress indicator is necessary.
IMM, text toollng is 2 parts
Creating and editing text
Displaying text
This tool does (2) very well. Youtube, hip-hop, songwriting all indicate that the audience wants less text and compressed content.
My favourite for (1) is Keynote (MacOS, probably Powerpoint, too, but, I don’t know). Keynote is a REPL for content creation. You edit text, Keynote changes the font size on the fly and you get immediate feedback on whether your text has too many words in it. Keynote, though, then tangles (1) and (2) together resulting in bloatware (images of slides), instead of separating the two aspects.
The best analysis of textual prose that I’ve seen is Pat Pattison’s work. There are ways to write text that result in more interesting text. Pattison analyzes and narrows it down. Pattison, ostensibly, talks about songwriting. Songwriting is about writing compressed text, how to punch it up and how to make it memorable.