I really like the Volt Nav system. I use it going to work and back because it checks for traffic on the route. Obviously though, I don't need the "normal guidance". It would be a nice enhancement to turn off the "normal guidance" and only break into the audio program when there is a traffic issue.
A kind of related thing would be if you are using the nav system to go somewhere you are moderately familiar with - it would be nice to have "less detailed" guidance, just enough so to remind you of major intersections.