I remove the category from the "must do today" items. That puts them at the top of my Outlook task list in a category called "None." That helps them stand out for me.
As for the outcomes, I try to keep the Projects list down to the projects I really intent to move forward that week. Anything else goes on what I call Future Projects (same thing as Someday/Maybe).
One thing that I think is important is that if you unlimited time to devote to each project and no other people who would be involved, there would be no need for the context lists. You would start on a project and just move from one action to the next until the project had been completed, then pick another project and start on it.
To me, the context lists come into play when for some reason you can't go further on a project (because you have to wait for someone to complete the next step before you can proceed, a certain period of time has to pass, an appointment pulls you away from the project, or you just feel like changing gears). At this point, you need a "bookmark" to tell you exactly where to pick up next time.