I'm a bit shocked that what you focused on with that navigation block is what is or isn't included. I rather dislike that block (despite having had a major hand in the current state of it). I have it completely disabled for the user I most often use.
The worst thing about it is that it doesn't resize. Well, more accurately, the worst thing about it is that it is pretty wide, doesn't like to render more narrowly, and so can force the whole page to render much wider than it otherwise could.
But allowing it to flow / wrap much more would make it suck even more in other ways. Having the relative position of a specific link drastically change within such a large number of links would often make it significantly more difficult to find the link you want (for returning users).
Going with what seems currently to be a fairly popular approach among more typical sites also sucks more in other ways. I frequently have significant difficulty trying to use the auto-pop-up style of navigation menu.
Then, comes the worst part. I have to very carefully navigate the mouse pointer to the proper link without accidentally allowing the pointer to temporarily slip beyond the bounds of the new pop-up (which would make it suddenly just go away -- something that I often have happen more than once before I succeed).
I think I'd much rather replace the vast majority of those links with a single link that goes to a page that lists the names of (and links to) each section with a short description of each. Each would also have another link that jumps right to the "post a new node to this section" form input elements.
And I might make that navigation page be static (and without nodelets) just so it loads super fast.
I suspect a large number of current users would much prefer to have the option to keep the current nav block (which is usually not "too wide" for the typical "I maximize my browser, just like every other window" user). But I think the above design would better serve first-time and casual visitors and would also make the site instantly much better at rendering on small screens much of the time.
I'd probably keep a "Tutorials" link in the on-every-page block just to increase the likelihood of first-time users giving that section a good look. But it would also be covered in the "nav page" (but with no "add new" link).
I guess that would come closest to being a "site map". But not quite.
In reply to Re: RFC: PerlMonks above the fold navigation (size)