[wilsonng]

OmniFocus seems better suited for the Runway, Projects (10K), and Areas of Responsibilities (20K) levels.

But to go up higher, it can probably be done but I tend to use something else outside of OmniFocus.

I tend to use mind maps as a way to define my higher Horizons of Focus. From that mind map, I'll create projects and areas of responsibilities inside OmniFocus.

If you like to think in a list fashion, you can try an outliner in your favorite word processor or in an outliner program like OmniOutliner.