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Re: "birds eye view" - I really like this idea, taken to the 'completism' level...
A number of text/code editors, have a "minimap" attached to the side.
http://did2memo.net/wp-content/uploads/2013/01/minimap-in-sublime-text-2.png
http://i.imgur.com/OIhkpfA.png
http://notepad-plus-plus.org/assets/images/docMap.png

It works as an enhanced-scrollbar, and as an overview, and it shows text-selections from ctrl-F.

I think something similar to this would potentially help us:

* To better understand the scope of an article/section/entry, upon first loading the page.

* As editors, to find & refine wall-of-text paragraphs.

* Encourage light-readers to scroll more, particularly if they see thumbnails of images - in the same way that good textbooks can use images as content-hooks.

* more?

It would need Increased font size for headings, to enable ToC-like functionality. And some sort of minimal-version, for users who find animated-aspects too distracting. What else?

It might be too complicated to be a global default (UX-wise, and/or Performance-wise), but I'd love to see something like this as an option (toggle or preference or gadget).