One of the greatest tips I ever got for interiors was to diversify the ceilings and floors. Adding, crossbeams, rafters, trims, patterns, different depths, etc can really make a room feel more alive and can help divide long rooms into distinct separate areas. The example photos are from the lobby of a hotel I built on my survival world. I used stairs, slabs, logs, and trapdoors to detail the ceiling and for the floor I used red sandstone bordering regular sandstone and chiseled bookshelves with a small red carpet.
by GanjiTheWise