In the interest of a more fluid drawing environment with fewer mouse moves, less clicks, let's please improve the"Change Active Units" widget in the browser's root level by converting it from a command that triggers a windoid with a units selector and OK/cancel buttons, to a simple drop-down. So its just one move to the browser and a menu elect rather than three discrete steps.
I prefer to design in metric, but all of my metal extrusions come in english dimensions here in Canada (and USA, I presume). So I'm often having to switch display units.