I got nothing special. My CWD stereo cabinet has drawers that hold the cassettes, two high for max capacity in the deep drawers or one high for full viewing in the shallow drawers. Yes, some are not needed as often as others. The drawers with two layers, the top layer is in some boxes one gets at Costco that are sturdy and hold a couple rows each and two boxes fit into the drawer side by side. Makes it easy to pull out a good selection or to reach down and grab an oldie but goodie.
The reels are in the cabinet below the system, each cabinet has two rows, top shelf and bottom shelf as these are the 10½" reels, The few 7" reels I have are stacked around the big reels.
So all the tapes are enclosed and should stay nice and less dusty than if they were out. LPs and CDs are on the opposite wall in open Franklin Mint record storage boxes. These are stacked four high per side open side facing the room. Tough getting to the bottom box selections compared to the rest but the software is available to view and play. Tapes are just better protected.
Hey I found a picture of that unit. The CDs and Records are now on the other end of the room instead of behind the speakers. The reels are under the center section and the cassettes are in the right hand drawers. A few double layers in those drawers. And since you didn't ask the MDs are in a unit on the side of the room. Maybe I need a library.