Over the years Muni costed out various trolley bus extensions, in particular Geary and the Noriega extension of the #7 Haight.

In the case of the Haight-Noriega line Willie Brown had scored the electrification funding in the Legislature but Muni management just lost interest and let the opportunity go by.

All the underground feeders from the B line are still in place on Geary AFAIK - when Sutter St. was converted to one-way, Post St. had to be wired. They tapped into the Geary feeder downtown.

Expanding Geary carhouse-Presidio Yard is a no-brainer but you run into the City's sick obsession with selling off Muni real estate, which went totally crazy during the postwar bustitution.