[jackie_w]

@David,

As I don't use KoboTouchExtended I'll restrict my comments to the first 3 Tabs.

Some general first thoughts:

• I like the "less cluttered" look.
  
• I'm not sure what the rationale is for what's included on each Tab. E.g, is there a reason why Collections/Covers/Uploads are grouped together rather than having a separate Tab for each? Similarly, Metadata/Advanced?
  
• Are Recommendations, Previews, Archived books classed as Metadata? When I see the word "Metadata" in calibre, I assume it's referring to data in my calibre library columns.
  
• This may be a bit premature if you're only at proof-of-concept stage but, I'll say it anyway If I was a new user wondering what some of these options do, I don't think I'd be any the wiser with the Tabbed display than I was with the old all-in-one display.

More specific thought:

• Using CollectionsGroupBox as an example - but also applies to CoversGroupBox, MetadataGroupBox:
  
  The first checkbox, 'Manage Collections', seems to be acting as a "controller" for whether to do anything with the other 3 items below (Columns, Create coll, Delete empty). If I have understood this correctly might it be better to remove it and have this checkbox belong directly to the CollectionsGroupBox parent widget. i.e.
  

  class CollectionsGroupBox(DeviceOptionsGroupBox):
      def __init__(self, parent, device):
          ... ...
          self.setCheckable(True)
          ... ...
  
      @property
      def manage_collections(self):
          return self.isChecked()

  I believe all the child-widgets would be automatically enabled/disabled as the CollectionsGroupBox checkbox was checked/unchecked, removing the need for manage_collections_checkbox_clicked()
  (see screencaps below). This 'run from source' thingy is pretty handy.

Final thought:

• What are the chances of bringing KoboTouch and KoboTouchExtended together as one driver so that it would be possible to send a batch of epubs as plain-epub or kepub as the whim takes me for this particular batch?