I've been experimenting lately with setting up a keyboard-only computer (a Pi Zero at the terminal and running i3-gaps, specifically) with a mind to making a more productive writering machine. Felipe Cortez has gotten a lot further than I have, using the Vimium extension to create a browser-based work environment.
• Put the keyboard on your lap and never move your arms
• One less USB port, maybe
• Set up a Raspberry Pi, GUI mode, without a mouse
• Look cool to your coworkers
• Make your life harder
Trying to recreate the simple, keyboard-only computer experience of my youth has been only partially successful. The three big problems are:
1) There's nothing simple about linux environments, it's a labyrinth built on half a century of technical debt, and the road to making them functionally simple requires a fair knowledge of the complexity. I might switch to FreeDOS for this particular project, but you know what they say about frying pans and fire.
2) The keyboard I've been using, the Vortex Tab 75, does some odd things that make it unreliable as a primary user interface device (a problem true in both Windows and Linux "modes"). I just switched to a Logitech MX Keys and it Just Works, so am making progress!
3) My own expectation to do all this by making a minimal system with no unnecessary parts (rather than just adding a keyboard-friendly extension on top of the slagheap a la Vimum)