One of SMART's shortcomings is that it does not serve Marin south of Larkspur, close to half of the county's transit market. Doodlebugs can't do this but electric light rail could. It wouldn't be cheap but that is the price of real rapid transit, especially when you have torn up the legacy ROW. You would have to widen the freeway alignment enough to accommodate a single support double track elevated down the center. Some overpasses would have to be raised and maybe some tunneling in Mill Valley, but the big upside is an operation no longer impacted by traffic, which can be quite bad at Sir Francis Drake.

SMART should have focused on an all day transit service replacing at least part of the existing trunk bus route. Even if it meant laying in a second track, even some street running(in Petaluma, for instance) and even if it meant going to war with the FRA over proximity to freight rails.

And I definitely suggest Golden Gate Transit should absorb SMART.