Okay, let me cover the basics again for the record: When you set up a Label Style - of any kind - you need to set your text sizes to what you want the final size of the text to be on the plot. Civil 3D then resizes the entire label based on the viewport scale to make sure that the text plots at x units tall; the same applies in modelspace based on what the Drawing Settings' Scale factor is set to. That's the basics that we all know and love. NOTE: It doesn't allow for plot scale, just viewport scale.
Now, if you're shrinking your paperspace layout by 20x when you plot, then of course your paperspace labels are 20x too small. Why do you shrink the layout at plot? Why not start with a sheet the right size in the first place? If you do that, your labels should come out beautiful.
Trevor
Message was edited by: T_Bernhard