Instead of or in addition to sconces hidden lights can add a general glow that bounces off the wall and into the room in an even subtler and more diffuse way. Cove lights are built into niches that hide the light source (often a plain LED strip) but hidden lights can also be obscured by medicine cabinets shelving or storage units.
If your cabinets don't go to the ceiling consider adding lights above the cabinets. Using a more powerful light source such as a T5 fluorescent increases the reflectivity of the ceiling thereby increasing the light in the room. While increasing light levels is important it is equally important to minimize glare. Use matte finishes to reduce light flares and glare.
A floor lamp nestled against a window is a smart substitute for daylight so that when the sun goes down an ambient glow will pour in from a similar direction to balance the central light overhead.