You know your own house better than anyone else; you've probably got rooms that you wish were bigger, or perhaps other areas where you'd spend more time if only they felt more cozy and intimate. The solution might be as simple as a new color scheme.
White ceilings and walls might be the "safe" way to go, but that hint of "Forget-Me-Not" in your floor tile, or other interesting but unusual colors in your furnishings, can make your house stunning when you look to them as a source of inspiration.
By using shades of such colors, light or dark, you'll accentuate and create the unified look that so many professional designers strive for. Colors give rooms their "mood"; that is, they stimulate feeling.
Cool colors (any that contain the primary color blue) make rooms feel larger and also bring a feeling of calmness. Such colors might be effective for making a west-facing room feel less hot and sticky on a sunny afternoon. Warm colors (which contain primary colors yellow or red) are stimulating and inviting, and are good for making large rooms feel cozier and warmer.
Some combinations of color create optical illusions - these may take you by surprise, so exercise care in choosing by holding swatches together and seeing how one color affects the other.
For instance, by placing white with any color, you'll notice that the color makes the white look brighter - and the white makes the color look darker than it really is by itself. Be sure to do this in your room's natural light at different times of the day.