Wouldn't it be precisely the very minimal movements that make the keyboard and mouse most expressive? If more grand movements were required, that means it would be more effort to express the same things.
Or maybe we're not thinking of the same "expressiveness"? Maybe you mean expressivity of emotion while I mean expressivity of ideas?
Give the PS4 "dev-game" Dreams a spin, you can program by physically connecting logic gates and moving wires and gadgets. You wiggle the controller to move around the screen.
Much less efficient but immensely more (visually and mechanically) satisfying than typing. I personally love it.
Depending on what you mean, there's some work on voice coding (dictation plus tooling, basically), or perhaps you want notebooks or literate programming?
Edit: With pen and paper you can structure your code however you want. You can use any symbols you fancy. I like blank paper, with no grid/lines.