>>1448260Here you go fren. Now, the idea is first off extend the SMART train to the south all the way to San Francisco. This ought to be done first in a viaduct along the highway, and then over Golden Gate bridge. I've read that the bridge is perfectly suited to add some rail tracks below the road level.
Then, add to that few LRT lines mostly to act as feeders to the commuter train.
Now, I've only focused on the area of southern Marin County, as you asked. The issues with Vallejo and Richmond would have to be fixed with a comprehensive Bay Area project.