It's just my opinion but I would ask myself why I am keeping this snake.
Am I a breeder, massive/producer/collector? If so then the least amount of maintenence and cost overweigh many other factors. Something that is disposable, cheap, and takes 2secs to replace works best.
Is this snake more of a pet?
Is the cage desirable as a display item?
If time and money were no option great efforts would be made for a huge elaborate enclosure that beautifully immitates the natural environment. This makes for a great looking cage and benifits the snake that much more.
An earthy or mossy type of substrate is picked for it's ability to hold the proper amount of humidity without remaining damp which allows for disease growth. There is a great article every month on keeping natural vivaria in Reptiles magazine.
I should add that personally I have cages of both types. The larger and bulkier the animal the harder it is to keep a natural setup healthy. For quarintine I always use newsprint to reveal stool consistency ect.