The pdz under the roosts definitely keep the coop litter cleaner, dryer, less smelly. I only clean out the coop litter once a year, in spring when I'm ready to clean up from winter. Then I don't put that much wood shavings in, since it will be warm, and then in the fall I add a bunch more...
Have you tried Sweet PDZ instead of, or mixed with, the sand on your poop boards? It's like 'super sand' and keeps the coop less smelly than plain sand.