Dave,
+1... I like that idea.
That is similar to what some scantools like the Genysis/Nemysis do... all pids are being logged, the ones visible on the screen are updated at high priority, the ones not visible on the screen are updated at low priority, and you can dynamically scroll/page up/down thru a long list of pids; it also allows you to move individual pids relatively up/down so that you can group pids together on the screen.
This allows all pids to be quickly viewed when I have no idea what I'm looking for when troubleshooting.