Custom playlists is also on schedule for next release. A playlist will be statically created on the DMM PC app, of course, not on the dune itself.
That will actually create a "custom album" that is shown and behaves as any other album but has user selected (cover, title, list of songs).
As far as a "shuffle mode" is concerned, this is possible on the dune (press ENTER + 7 on the remote control). It is also possible using the DMM web app.
On top of "custom albums" i.e. playlists, next release will also have "Selections". A selection is a collection of albums, artists, genres that gets a name and a cover. Eventually it behaves as a "custom genre" that ends up having a user selected set of albums.