No silly messing about with different organisations fighting each other over who gets to pay how much to whom and considering that of more importance than what happens to the passengers. More versatility with far less incompatibility of stock, and crews having a wider range of route and traction knowledge. Plenty of spare stock for when it was needed instead of paring everything to the absolute minimum so there's only just enough to run the normal service if everything goes perfectly and falls apart if it doesn't. Also spare locomotives to rescue failures, and use of workarounds like using the following train to push a failure on to the next station. Absence of the idea that you can't do anything to help a failed train without killing the passengers. More versatile track layouts allowing more possibilities for the necessary unusual movements. A tremendous set of worked examples to demonstrate the surely rather obvious point that you can handle disruption a lot better if you don't cripple, forbid or abolish the things you need to handle it with.