I live and grew up in Baltimore, which employs mass transit, but not on a “city wide” scale. Here the majority use the Light Rail system, which is a single line through the city north to south, with the little used single line subway going east to west.
In places like DC, SF, LA and NYC, you can go anywhere within the city, and in some cases, outside the city, by simply catching a bus and riding to the nearest train station. Baltimore is trying to become more like DC, but we’re still a long way away.
I think a monorail system might be a good idea, but it might be a little more complex than it seems on the surface…