Administrators
Administrators need a central place to configure the whole site. That central place should be structured in the modular way drupal is built up. This should be similar to Gconf, the config-panel in windows, or control-centre in KDE. Themes, modules and global should be the top-level of the configure pages, but only leaves of the menu should contain forms in which configuration can be edited. Branches/trunks might contain descriptions or help, but not forms: For example /settings cannot contain a form, if /settings/navigation contains one. In the last case, /settings should contain a short description, and possible errors, on what /settings/navigation and all its brethren contain.
The structure should be very flat: only two levels. And the configuration should never be mingled into the site structure, as seen by visitors: a site administrator will only once configure the search and will thus never ever need to see a configure tab on his search page: There is nothing to configure there at all!