Is there any way to reset a menu's default order (e.g. Management Menu)? I have installed Drupal Commerce Kickstart and included with the distro is a mega menu. It also restructures the menu items to a more "End-user friendly" order. I personally prefer the default order that core gives you. Is there any way of resetting the "Management menu" to it's default order (without manually reordering them again)?

This is what it looks like after disabling the mega menu and enabling good ol admin_menu
Not that i'm aware of.

It sounds like the mega menu being active is firing something like a hook_menu_alter to be evaluated by Commerce -- they've hardcoded their own ordering because its more "user friendly".

hook_menu_alter overwrites values that the menu had, so drupal has no knowledge what the default ordering was. If the mega menu is active it forces their ordering, if it isn't you get the default ordering.

You'd have to look in Commerce where they add the custom menu items, or activate the mega menu and see how their adjusting menu #weight values.

You could then write your own hook_menu_alter that undoes their changes.