We have a slide out tray and use plastic storage boxes. We are full timers and my spouse is a master packer and does a great job of stowing everything so it is secure.
Look over in the modes section, a number of good Ideas in things for your storage area.
Use Small PVC pipe's connected to the overhead for fishing poles, bought a large water pipe, glued fittings on the end so you can screw ends on for the sewer pipes, attached to the front panel of storage area an put a small drip pan under the one end to catch any water that drips when storing my sewer hose after clean them for storage.
I put in a MorRyde cord reel in for my 50amp power cord about 10 inches away from the storage side so I can put my step stool side of it, bolted a heavy plastic tray on top for all my power adapters ...
If you look around thought different brand reflectors/forms such as Kz Family form , Forest River form, Montana Form etc you can tons of ways to store stuff in 5th wheel, TT and DP's in storage areas ...
If I thought I really had to, the underside of the above flooring has exposed aluminum tubing supports. I could always make partitions attaching from there to the basement flooring. I am however, reluctant to ever drill any holes regardless of how minor. It's a boat thing.
I understand what your thinking if your new storage is like my new Crusader, there are two drain pipes running thru my one large storage area, hanging down on a couple flimsy hangers 4-5 inch's.
I too am looking for ways to keep things from shifting around or more likely me putting a storage bin back in and hitting the pipes. I should have noticed the pipes before buying this unit but it had so many more nice to have things our Outback didn't have I must have just overlooked them in my happiness to be using auto level and inside utilities in one place, and many more.
I wlll be watching this thread in hopes of good ideas for storage area organization.
Too much stuff means you're not likely to be able to get to what you need. And then you may as well not have it in the first place. Keep your storage accessible, not crammed.