A notification or ticker bar at the top or bottom of the dashboard would be cool for displaying important notifications that pop up from time to time. For example, it could be a red horizontal bar that pops down from the top of the dashboard when there is something to display, like a tornado warning, or heavy traffic on your commute. Notifications done that way would catch your eye when they occur, but not take up screen real estate otherwise. I don’t know which would be better, to push the existing content down and squish the display vertically to make room for the notification bar, or to layer the notification bar on top. Probably the latter. Or, if layering isn’t possible, even just have an option to define a static thin horizontal bar space at the top and/or bottom of your dashboard, which would hide (with nothing there) when nothing to show.
I suspect implementation could be difficult, but just an idea.