Not that I disagree, but at what level do you establish proportional representation? At the state, county, city/town/municipality, somewhere in between? Current

Not that I disagree, but at what level do you establish proportional representation? At the state, county, city/town/municipality, somewhere in between? Currently, I think the boundaries are drawn ad-hoc but loosely defined by population, geography, and demographics that benefit who ever is in charge of the pen.