Interesting you mention the particular problem of Birmingham New Street. One of the effects of the new timetable is to force many more journeys to connect there.

For example, Rugby-Carlisle, Leicester-Liverpool, Northampton-Preston, Burton-on-Trent-Crewe. All should be possible via simple connections to the high speed WCML services, but from next month, at most times of day, passengers are likely to be routed via Birmingham.