In a renovation on the other hand we have to consider what effect a new skylight will have on the efficiency of the existing building. In some cases the additional sunlight (and therefore heat) can help reduce the amount of energy needed to heat the house. It depends greatly on the local climate but also on the design of the building envelope of the house.
Adding lights to stair risers is beneficial since it can be hazardous negotiating stairs especially at night. Staircases are often enclosed so light them from the sides or embed lights in the risers as a design element.
When hanging a light over a table or a kitchen island 28 to 34 inches is the recommended distance from the bottom of the light to the surface of the table or island. However the size of the light makes a difference. In general a smaller light can be moved lower and a larger light can be moved higher.