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.
Don’t limit lighting to downlights. Depending on the location consider wall sconces or uplighting to create a softer ambiance and avoid potentially harsh downlighting that can cast ominous shadows.
Another important aspect of lighting a space for those with diminishing eyesight is visual cuing. Visual cuing provides an additional reference point for judging distance or depth when entering a space or approaching objects. The lighting at the base of these cabinets or toe-kick lighting contrasts well with the dark floor and midtone cabinetry creating a readily visible contrast. But people will just think it's cool.