In the Details view mode I know that when a folder is selected, I can use the left/right arrows to open or close the folder contents in the view. What I would like is to be able to to recursively open all folders under the selected folder with a single key press.

It would also be useful to be able to collapse the subtree back to a single level with a keypress or alternatively close the folder and open again to a single level. Currently closing a subtree then opening restores the previous subtree.

The MS-DOS XTree filemanager used the shortcuts:
'+' open single level
'*' recursively open all subdirs under current dir
'-' close the subdirectory contents

So that is one possible set of short cut keys to use. It has the advantage that all three are easily accessible on the numeric keypad.

It would also be useful to be able to navigate to the next or previous directory when a subtree is open.

eg

  A    (A currently selected)
  | a1
  |  | aa1
  | a2
  | a3
  B

be able to press a key to go from A to B in one step without having to step over a1, aa1, a2, a3 or having to close the A subtree first.

Also, as far as I can see, the current navigation shortcuts (arrow keys) are  not documented in the Dolphin Handbook.