Awesome project!
I've spend some time on sites like Keyhero and 10fastfingers since I really enjoy typing, but sites like those ultimately feel time sinks since there's very little to gain after you reach a decent WPM.
This site feels meaningfully different since I get exposed to the literature as I'm typing. From a quick glance it looks like the UI is really clean and the text is easy to read.
I'm looking forward to using your site in my free time.