To piggyback on what Ed says, I’ve moved away from any desire for basement railroading. I simply find that a bright and cheerful naturally lighted area is much more conducive to my model building happiness.
If I could reach nirvana it would be with a huge “train sunroom”. Looking at the beauty of Erik’s trains or a Lee Turner model in natural light is a wonderful thing.
How to build it for a railroad of the size and scope of Ed’s is a complete ‘nother story.