My site currently has 50 menus under "appearance". I expect to add more menus in the future. In this situation, the wordpress menu admin is not good enough. Navigating between menus and adding a new menu is difficult and you have to keep clicking on the top menu navigation slider.
I suggest 2 improvements to the menu admin area.
1. A separate button (not part of the top slider) to click "Create new menu".
2. A drop down menu to navigate through existing menus.
Keep up the good work