We found the low profile storage bins with wheels so two of them can be stacked on top of each other. We keep extra bedding and various things inside just in case we have guests that want to sleep over.
We also store our folding chairs in the back, as well as our outdoor grills and my collapsing ladder. It works well to put heavier things back there to minimize your tow vehicle pin weight, since the compartments are behind the rear fifth wheel axles.
Hope you never have problems with the door latches. but if you do (as I did on one of the rear doors), you will have to take everything out of the compartment and access the back side of the door latch from the other side of the camper through the opposite door. That would not be fun if you had a slide out tray installed.