The most efficient would be 3 major east/west lines, Boston to Seattle, DC to San Francisco, and Atlanta to LA, connected by a series of north/south lines to form a grid. On the east coast, just extend the Acela down to Atlanta.
The most efficient would be 3 major east/west lines, Boston to Seattle, DC to San Francisco, and Atlanta to LA, connected by a series of north/south lines to form a grid. On the east coast, just extend the Acela down to Atlanta.
The biggest concern with that setup is how inefficient it is to reach the Pacific Northwest region, LA is a serious bottleneck on top of being a common endpoint in and of itself. A line that goes straight to either Seattle or Portland from the Northeast simplifies things a lot.