[redrobein]

I wonder how well an eye tracker + keyboard keys bound to clicks would work (ahk?). From qhat I've seen they're pretty accurate and it'd be very low physical effort.

Although I think think the better answer here would be just using a keyboard. Use a keyboard layout like colemak. Support your arms somehow. Use software that support keyboard only use. And use macros to make things you can't do or complex tasks easier.