Perfect thinking.
You just made a great case for regional express rail.
Something that is not quite HSR, over 200 mph, but is faster than car travel, to provide affordable transportation up to 200 miles. The South African Gautrain is a perfect modern example. Running at 110 mph it easily beats auto travel.
Regional express rail is less expensive to implement than HSR which makes it a cost effective solution to bridge the gap between subways/commuter rail and long distance HSR. In a cost comparison it holds up well to travel by car or bus without subsidies.
Put on dedicated express rails, with well planned schedules and stations it would do nicely in your example.
