I know a lot of themes let you edit the horizonal menu bar under the header, but in the basic wordpress install, it is still a bit daunting for the newbies to re-arrange/edit the navagiation menu.
If it could be a seperate tab to the left in the admin section, maybe called "Navigation", an in it you you could choose the order of the top menu bar, including drops downs manager, if you like.
Also, a spot to tweek the css look of the bar right there, say, rounded tabs, colors, inset, what the links actually say, shadows, etc, etc, but in GUI form for those of us who still find CSS daunting.