Here is another thing the developers should be doing.
When one opens viewport properties in Pagespace, and toggles on and off visibility of layers, the layer visibility should toggle on, and off, in real time, BEFORE one clicks OK in Viewport properties.
Pagespace code needs to be updated. It is just plain silly â€“ the functionality of layers in Pagespace. If you are dealing with 40 or 50 layers in viewports - it is a PIA to toggle visibility going down the list. You have to sort through, and remember what is on all 50 layers and hope your settings are good before you click OK. Why not just have visibility instantly toggle on and off before your eyes, before you click OK to make your viewport layer settings?
Unless you write down on paper what is on each and every layer how can anyone remember what's on 50 layers?