How would non-web savvy editors add new pages if the menu is hard-coded in the nav template? Thats not a workable system.
The reason no one mentions Joomla is because its badly in need of an overhaul, although it has the most plugins and components, its all thrown together any which way. Anyone who has used Joomla, with Virtuemart and a gallery module plugged into it - and then tried to teach someone else how to use all the seperate backend functions - whilst avoiding the bugs, will feel the pain. Its just not a professional option. Its fine if you are running your own site asa hobby - its not something you can rely upon to be stable for selling - nor is it something I relish the thought of training people in using.
PGO, the problem I've found with CMS made simple is that although its slick at what it does, it simply can't handle larger scale sites. The way content and the menu is dealt with through the same system is brilliant for your average site - but for really hefty corporate jobs its not even a contender.
IBM chose Drupal for their intranet, and they have a series of articles explaining their thought process as they put it into use - might be worth reading those:
Using open source software to design, develop, and deploy a collaborative Web site, Part 1: Introduction and overview
The way it treats content as 'nodes' - be it an article, or an image, or whatever - is odd, its lack of built-in admin backend is even odder, but with a bit of code to detect if the admin is logged in it can be made to switch to a seperate admin template. Its advanced menu systems are a real head fuck... it took me days to comprehend the taxonomy module... I didn't even know what taxonomy meant to start with. But its powerful. I've not yet had time to roll out a large site on it (beecaus they also won't risk a switch at my workplace) but from what I've had a chance to read and play with in my own time, I think its got the right balance between flexibility, stability and learning curve. I mean people say Typo3 is ultra-powerful - but its learning curve is insane. You may as well learn PHP and hand code what you need yourself than learn its own proprietary language.