Page editor navigator is unusable

[sque]

The page editor navigator on the left sidebar has some serious
issues.

• If you have a lot of pages, it is very difficult to find what you
  want.
• If you to move a page, it is pain in the ass. As the draggable
  object jumps around and it is very easy to ruin all the structure
• It is difficult to understand at which level you are, as it
  depends only on the left padding of the entry.