Think like a photographer would.
1: the actual room lights are there only for show - you use a key, model and fill lighting strategy with independent illumination - ever attend an interior photo shoot? Why are they bringing all those lght when we can already read the newspaper fine?
2: Once you've modeled the room with photo lights, the last straw is to bring up the ambient to compensate - a cheap, but necessary, draftsman's trick.
3: There is no such thing as a white light or a white surface. Everything is either yellow or blue. In California, brownish or mauve. Doing this will immediately bring life to your scene - and this is from a guy who dresses in black.
4: There is no such thing as a smooth surface. What makes for interesting interactionbetween surface and light is texture - for plaster, a little noise is not only more realistic, but conveys a sense of volume. In lightworks, add 1% roughness to a smooth material.
5: Background image should equal foreground in sharpness and contrast, otherwise looks like painted backdrop.
6: compose furniture to lead the eye into and around the space, not appear like leftovers at smoke-damaged clearance sale.
7: crop your stuff tight.
Dwight Atkinson