The reason for the above is that the sitename shown on large screens is derived from the global area "Header Site Title", same as Elemental. However your sitename may not be the same. The sitename is used in the mobile nav, not the above mentioned Header Site Title.
If you are using a base elemental install you will find a plethora of new areas in the main content area to give you amazing layout flexability.
Please report any issues asap. If you need a custom layout just drop me a note.