Virtual Device: Ability to have it's variables be local only

Right now, when I create a virtual device, any variable associated with it seems to only be global. While this is great when needing to have global variables (which I currently use), it would be nice to be able to create a list of variables that are unique to a particular instance of a virtual device (maybe a checkbox option that says make this variable local only).

Usage case for this would be:
Would be able to create several virtual devices that each have the same-named variable, then I could put the virtual device in a device browser and reference each device by the same variable name (same idea as using the reserved variable @Device).

If this were possible, I could build a virtual device that would contain any combination of real devices that I so choose.

Example usage:
I have a few pages that contain repeating groups of data from several different devices of my hub (for example sprinkler zones - which have several devices). Instead of copying the controls for each zone onto my page, I could create just one page browser sprinkler zone, then have a virtual device for each zone that contains all the different device data together. I could then just plug in each virtual device for each instance of the page browser on the screen, which would greatly reduce the overhead of repeating controls having to be drawn etc.