We may want to officially make use of this, redesigning Composr to have a single drop-down menu that spans all zones. Also redesign the CSS to be a lot simpler - remove zone menus and top menus, leaving just dropdown, embossed and tree. Place each menu type in it's own CSS file, and use "mix-ins" to avoid repetition (or possibly just copy&paste, if it makes things easier for themers).

For mobiles, it might be best to have a menu button that pulls out a full screen accordion-based navigation. I'm not sure, it needs thought.