These are all great suggestions! I might recommend the Glade Bookshelf over the Manor Bookshelf, though that's a tough choice. Each has elements of the FF6 bookshelf; Glade has a squared top, but Manor has the lower cabinets. There is a treasure chest, the Dead Man's Chest. For the secret path, perhaps set up some matching partitions so there's a narrow crawlspace near the wall. You could improvise an outdoor raft with a lot of overlapping Firewood.