An "expanded" Schengen Area that crosses the Atlantic and Pacific oceans and brings Canada, Australia (and Japan, maybe?) into the fold would be an incredible thing. I'm all for it.

It would be nice, but it's too high a bar to set, as the visa policies differ significantly between the three.

There is a real danger the Schengen agreement itself will collapse in the upcoming years - Germany is already ignoring both the Schengen agreement and its own courts by keeping border controls.