Found Method for Waypoints
I just found a means of "turning off" the display of waypoints:
1. Set up a waypoint category that you won't use for any waypoints. You could call it "No Display".
2. Choose the waypoint tab and in the "Show Waypoints In Category" box, select that category (in this example that would be "No Display". Since there are no waypoints in that category, no waypoints will show on the map (nor on the list under the waypoint tab).
3. To return to displaying your waypoints choose "All Categories" in the Show Waypoints In Category" box. They'll all reappear.
Combining this with the transparent suggestion from 9Dave works, but I'd still like a simpler means for tracks & routes than setting them to transparent.