Give more focus to your content. With a Metro style app you give users immediately focus on the primary infos, increasing the usability and reducing the distractions.
Use the ApplicationBar to show contextual icon action.
Implement the navigation in pure MetroUI style, use back-button and the header menu to provide simple ways to navigate to other pages.
Create charms panels to show contextual settings.
With the awesome IcoMoon font icon set, you can use hundreds of font icons with any color and any dimension.
Show messages, warning and errors like Windows 8 do.
Show selectable lists of elements.