Finally grokking the utility of `C-c [` / `org-agenda-file-to-front` and `C-c ]` / `org-agenda-remove-file` to manage agenda files rather than my previous habit of "every org file in this directory, recursively."
Now, basically, the tasks in an area or project—sorry, "campaign" or "adventure"—only show up in my agenda when I care about them. Don't need to filter or cancel. Just "I'll get to the Luanti ideas later."

