| .... It's hard to see the signage, there are no lights to
speak of, and trying to read taxiway diagrams with that feeble red
cockpit light is useless.

| So turn up the lights so you can see the diagram.

Modern aircraft don't have only red lights in the cockpit,
lots of lighting and pilots carry flashlights, pen lights
and can study the diagrams in the office too.

Try a green or blue LED light.
It won't destroy your night vision and provides a brighter light.