Is there any way to change which roads are shown on a particular zoom-level?

[pdrkeg]

I may be missing something, but is there a way to show minor roads even when your zoomed out a little?  In the country you can only see the minor road if you are zoomed way in, this prevents you from seeing on the map which roads are thru-roads etc.  Is there an option for this somewhere? 

[oldracer]

Every GPS I have owned had the roads that you could view set by the software and was not changeable by the user. This was true even for the map on my iPhone and the one in my X950BH head unit. There seems to be a wide view area with few streets and then at some zoom in level lots of them show up with few names and zoom in further and the names show but with less streets on the screen.