Changing Polygon Outline thickness by scale

[CalebWilliams2]

Good afternoon,

I need my data to stay in one layer, and exist as polygons, but I also need to be able to see them from pretty far away. So I was wondering if it was possible to have polygon border thickness change with scale. Getting thicker the further you zoom out. 

[DavidPike]

I had a quick test of using an expression based on map scale in the new map viewer (previous beta).  But I wasn't able to change the outline thickness.  You might have more luck as I may be missing something simple.

This was the quick expression ('Styles on the rightHandSide) -> Choose attributes - New Expression) Then I just chose Types(Unique Symbols) and set the properties for the the current and 'other'.

if ($view.scale > 100000 ) {
  return 1
}
else {
  return 10
}