If you decide to put in a light, look for one where the lens is installed in the pool wall, and the light goes in it from the outside, and make it an accessible point. Then, if the light fails you can access it from outside the pool and not in the water. Also, for safety, I would STRONGLY recommend you ONLY use a 12volt light in your pool, and not a full voltage one. And, of course, it must be on a GFI circuit.

I have two 12volt lights in my pool, and, while we don't use them much, we do use them.