I'm not sure if Unity has a design problem. If the Launcher is hidden you can bring it to front by moving the mouse over the home button or hit the Super Key. So far, so good.
But what is on Tablet Devices with touch panel? Intuitively I would "click" in the corner to show the launcher, but a click will open the Dash.
How should that work on a touch device? Do I have to "drag" my finger into the corner? Will touch devices have a "menu button"? Will there be a gesture to show the launcher?
The launcher can be revealed using a four-finger drag, starting in the left half of the screen, dragging to the right. Or, it should be able to be revealed that way, I don't believe that work's been done, patches welcome :-)