Desire to reliably get to my destination before nightfall.
Tricia we travelled from San Francisco downtown to Los Angeles in February this year, using a Thruway bus down to San Luis Obispo then Surfliner.
We too were frustrated by the lack of departures of the Surfliner compared to the past but having made this trip before were prepared to adjust our travel as it was such a wonderful journey. The bus is a great addition to the journey as it uses the Daly City and Palo Alto side to get to San Jose. The bus is not crowded, well almost empty actually and the ride is interesting and scenic in places.
The bus starts in SF about 10am from Mission Street bus stop, then down to SLO with just a handful of stops, but you have to get the mid afternoon Surfliner arriving just before 10pm in LAX so may have to hotel across the road at the Metro Plaza or similar before continuing on the following morning, or catch the late night Surfliner onwards.
Reason I wrote this is to explain it is possible to bus and train south from SF, and we enjoy the journey so much we would repeat it often if we could. The 4 hours on the bus adds to the journey for us as it creates a contrast, just a personal opinion.