I'm not sure if this has been mentioned but if not here's something I'd like to see.
How about adding the elevation so that it shows up down at the bottom right corner along with the Lat/Long based on where the mouse is located. At the very least show the elevations of the higher hills and mountain passes and also the grades so those of us with larger vehicles like trucks and RV's can make choices on whether we want to take a particular route.
Trailer Life Campground Navigator Mapping software has this, at least to a degree they do, and it's primary purpose is for campground locations.