That is what I do, I create a rule to pads with creepage and rely on my calculations. I'm rebuilding my current switch board to make it safer to use in more polluted environment, I need to use one outside (in a box, but better safe than sorry), and in a bathroom. I think that the main problem with the pads and traces spacing is the design constrains. I need to keep it in a 5x5 cm board and that is not easy, especially when you have a AC and DC circuit! I never considered the distance between AC and DC, and that is the main reason for me to rebuild my boards. After reading your post I made some researches, and I found that I had a design problem. Like you stated, I'm not a electrical engineer, and we are always learning