Since you say you have a big night light is sounds like you are an experienced night diver. I gave my BIG light away before I moved her. For one it took BIG batteries and they are expensive. I now use small halogen type lights. You don't need to light up a large area. I also have a laser light that works wonders for spotting critters without scaring them off. When I was doing still photography I found this very useful. You will be amazed how much light there is even with your light turned off.
Now that I do video my lights on the camera work well in place of lights. Fortunately there are three levels of intensity and I can turn on just one and keep it on the lowest level until I am ready to start shooting.
Do go to the site on a day dive prior to the night dive. It is nice to have scooped out the terrain.
A good dive shop will know the tides and not take you out when the current is running too strong, especially if it is going out. I have had to claw my way along the bottom in order to get back to the boat. This is not fun.
We all have our favorite dive operators - mine is Hustler's Eco Tours at the north end of town.