Personally, the bagua is a map of energies running through the earth. While they may be affected by astral bodies, their location is determined by the energy flux of the earth. That's why I still go for the magnetic view point. You're entitled to yours, of course.
I have no problem at all with you using what works for you.
I'm just more interested in results than theory. If I followed every theory to come out of Chinese Feng Shui (and I assure you there is one born every day) Feng Shui would be a mess. The history of Feng Shui is not one of information, nor of benevolence, but of serious misinformation in an attempt to get an edge over rivals and imperial suppression as well. You are attracted to what's right for you at the moment, so I do not feel the theories are wasted. They just work for different people. It took me eight masters (including at least one who pushes the southern atmosphere thing) before I found what works for me. My philosophy with this is: If it works, I'll use it. That southern hemisphere thing just hasn't done it for me. To this day, it makes no sense to me even on a theoretical level - if we were truly mapping the location of the sun, arguably the greatest yang energy you would find on earth, the enhancer for wherever it is would be a parasol.