Wire Rack Works well
I had a dead space in the center section of my gun safe- between the long guns and under the storage cubicles. I built a PVC pipe storage frame about 24" tall and 10" wide, with the finished wooden top angled down at ~30 degrees. I drilled four shallow holes into the wooden top to match the feet of the pistol rack (the first version you displayed) so the rack stays put. It holds 6 of my N-frames like a champ (27s, 28s, and 29s). I also put a horizontal shelf down near the feet of the frame to hold ammo, etc. I put the guns into the rack barrels down and hook the hammers under the wire of the rack. Makes a nice display, utilizes some wasted space, and handles everything from 3-1/2" to 6-1/2" bbls. I've also had 1911s and Model 15 snubs in the same rack. I'd recommend those racks.