I've found AutoCAD can operate similar to how you describe Altium, in that pressing 'l' and enter gives you a line, typing 'str' gets you stretch, 'tr' gets you trim, shift-clicking with trim gets you the opposite of trim - extend. The command line has autocomplete. In this fashion, one hand operates the keyboard, and your other stays on the mouse.

I quickly fell in love with this interface and immediately switched to using the command line for the vast majority of functions.