8.5Mb is a little too much for editor named micro. Whole DD-WRT/OpenWRT Linux Image is twice smaller.

And kilo[1] is 28k but it doesn't have as many features. Also a "keyboard" vs "keystroke" editor, editors built before ginormous keyboards became ubiquitous use various keystrokes for commands, ones that came to exist in an assumed presence of a ginormous keyboard use special keys for commands. (example, if the only way to move the cursor up in your editor is the cursor up arrow key, you are a "keyboard" based editor. Not that either choice is better or worse just something I find an interesting distinction.

[1] https://github.com/antirez/kilo