These are the problems with the corridor pattern. I'm trying for a compromise between a realistic layout and the original one.
I simply cant bring myself to have a world where miners are tunneling around 10 wide sections of rock just for fun. I am using features suggested by the random gen to turn some corridors into rooms. The 3x3 rooms with the central square are becoming stairways.
This then is the modified layout. I have only removed what I consider the worst offenders. I have tried to keep the size and general orientation the same.