So Lawrence, in terms of navigation, there are 2 thought processes
- Dynamic based on Tree Structure
- Manual
Dynamic on tree structure can be nice as when you add a page, it's added to the menu. Great for things like blogs and stuff.
However Manual can be better if your want your menu to look a certain way, be structured a certain way, OR if you want to employ things like Mega Menus.
I myself have created a system where the navigation is "Manual" but you can select a page to get the link and document name from it. Custom logic could be added to make some parts dynamic (such as a blog listing) and others not as well.
So it really depends on your needs.