[Brian]

As you mentioned, if you select/focus on a folder in the sidebar, the outline pane on the right of the OmniFocus window will display the contents of that folder in an outline.

That's generally how I manage large projects. Create a folder for the big project, then have the sub-projects in that folder, in rough chronological order. (Initial subprojects at the top, then later ones.)

When you say "splayed out" do you mean in a mindmap-ish diagram form? If that's what you need, you could export from OmniFocus to OmniGraffle, I suppose, but that's not how folks generally use the app. The list approach that OF takes seems to work for most folks, but "most" and "everyone" are different things. :-)