Nice job! First thing that jumps out at me is that the scale of the floor is way too large. If you look at typical herringbone floor patterns, each segment is usually no more than 1x1m or 2x2m. Should be as easy as increasing the texture tiling or scaling up the UV of the floor :)
Next up I would look into lighting. Not just from a technical point of view but also set dressing. Living rooms where you only have one white, main light look super flat. Think: where would you put lights in your living room? Would you place more warmer lights perhaps?
Unless you don't want windows, adding a few windows will also introduce some nice indirect lighting if you're going for a daytime scene.
