Welcome!! We also have 264BHW and have done one camping trip so far. I use some 6"x12" 1/2" plywood under stabilizers, works just fine and easy to pick up and store. Have added a propane cover, surge protector (Amazon), WD/Equalization hitch (from dealer slightly used), and had brake control prior.
Some things I've built for inside, shelf system surrounding the mirror (7 separate shelves) as there is no medicine cabinet, stool that also serves as an ottoman also, magazine rack (on back of dinette by door, and a TV shelf above the dinette well below noted TV mount location, this for our 32" that folds up when TV stored so have full use of dinette (note have bracing board on back of wall and used bolts to secure).
2015 SLX 264BHW
2007 RAM 1500 5.7L - tow and brake setup, Equalizer 1000