Here's an idea for an extension that I'll probably never get around to writing (but one of you might, perhaps for the extension contest!):
Overload Alt-(Left|Right)Arrow, the history back and forward keyboard shortcuts (Cmd-Arrows on Mac), to create an Alt-Tab-like experience with a row of thumbnail previews to which you can navigate by holding down the Alt key, pressing the arrow keys multiple times until you reach the target page, and then releasing the Alt key.
In other words, do the same thing for history navigation that Dão Gottwald is doing for tab navigation with his Ctrl-Tab extension.
(Bonus points for version 2: track non-linear meanderings and expose them as parallel tracks to which you can navigate with the up and down arrows.)