I like the little day bed and the window and beat board walls. day bed on plywood base with built in table. we would put the long edge further back for under the bed storage space. I also would want to paint it like white or something.
suitcase halves as shelves! i have not seen them used this way before (usually the suitcases are cut in half horizontally while closed--these are halved by removing the hinges, which keeps the structure intact).