In the shower area, after (or during!) a good warm shower....use a net "pouf" and body wash to quickly wash down all the surfaces in the shower area. You would be amazed at how well this works. All grime, soap scum, water marks, will come right off. After the wonderfully clean shower dries, then put a coat of rain X on the vertical surfaces to help keep it clean and shiny even longer. You really dont need fancy bathroom cleaners at all. And all those other bottles just take up more precious space.
I clean the toilet with the same Dawn and Calgon stuff I put into the holding tanks. Fill up the bowl with water, add the dawn/calgon, scrub the toilet, and flush down the tank. Fill up the bowl again and rinse. Adds additional water to holding tank and again, no special/harsh chemicals are really needed for the holding tank either. Dawn and Calgon works great for tanks and cleans toilet too!