You are thinking in the right direction.
HSRs niche in transportation is on medium to long distance transportation between cities. Cost effectiveness seems to start in the 200 miles or more distance between stations, but in high traffic corridors it can be as short as 100 miles.
HSR should not be a commuter rail that stops every 10 to 30 miles like the as designed in the California HSR project. HSRs big advantage is speed. You negate that speed advantage with numerous stops.
In the case of land expensive California it is much better to let existing regional rail systems like BART fill the gap for the last stretch into most cities than to spend the money needed to bring HSR into the heart of a city. The discussion of moving the LA station of a once proposed LA to Las Vegas HSR to a point nearly 100 miles outside of LA was stupid because they were planning on car traffic to bring the people to the train. There was no regional rail link.
Linked into regional rail the HSR terminals become your regional rail hubs. The idea is to give the customer options for their long distance travel. Right now many people drive 20 / 30 miles to a regional airport for a 200 mile+ flight. Driving to the regional rail hub would be no different, but properly a implemented HSR/Regional rail system could have some big advantages over regional airports.
First, properly implemented HSR should be competitively priced against regional air without government subsidies for either. At that point value added services provided, food or WiFi for example, and customer service are your competitive points with regional air.
Second, the regional HSR train hubs should be designed from the start to be linked into existing regional rail systems, like BART, and bus systems. This gives the average person additional options on how to get to the rail hub other than driving a car.
One other side note. The state of Californias decision to contain state costs on the HSR project by pushing the local infrastructure costs, new HSR train stations, access roads and parking garages in particular, onto the local cities and towns would be illegal in some states. The NH State Constitution specifically bans such legislative mandates from being imposed on local governments by the state government.
