Sleeves for future lighting are the best option to avoid having exposed wires ran later on. 3/4 inch blue flex pipe is great; it doesn’t crimp and can be used for low voltage and smaller diameter fiberoptics.
Landscaping lighting by itself can add a nice effect and a light behind a waterfall sheet accents the clear water. Fiberoptics (below) are more dramatic because the color can rotate or be fixed on a particular color.
LED lights are the emerging technology and offers many economical alternatives.