A very comprehensive reply outlining Feng Shui.
The way that I perceive things is that there are only two certainties in this life, the first is that we are born and the second is that we die, everything in between these two certainties is transmutable.
Now when I look at what you term the three lucks (and I personally do not perceive that I form my reality around luck) which would make me dependant upon chance, which I have to admit when I was younger and life kept biting me in the backside it did appear that way, but now I have a different understanding which works upon design rather than chance.
You outlined the first luck as:
Heaven luck = our karma given at birth and the help we can get from the spiritual realm
I perceive that we choose the type of parents and the type of lifestyle that we wish to experience, as well as any challenges that we might wish to have a go at overcoming before we come here.
As for help, we all get the same nonjudgmental help to create whatever our underlying thought patterns and beliefs are showing the oneness of consciousness (my take on spirit) that we wish to experience, in each complete experience as we experience it. There is no right or wrong in this equation, we are free to experience whatever we choose to experience in whatever way that we chose to experience it; should the experience end our existence here, then that is an experience in itself.
You outlined the second luck as:
Human luck = our free will, intentions, energy levels, our choices to build a different karma
I perceive this as our thoughts create our realities, or to put it into the correct terminology then as above, it is actually our underlying thought patterns and beliefs which has the power to mould reality around them, our everyday aspect of consciousness (thinking mind) might well be at odds to our core way of being, so saying to ourself that I want something, when our core way of being believes that we are not good enough to get it, will not let it happen very easily.
You then outlined the third luck as:
Earth luck= the influence of Earth on our lives, this is what Feng Shui deals with.
I perceive this as a two way street, the living planet can exercise influences upon our life choices, but then our life choices can also influence the planet.
It is a problem of modern living where people have lost contact with the natural rhythms of the world that we live with, I do not perceive us as being separate from the planet or what people call spirit, I perceive it all as one, when we are in harmony and experiencing oneness, then life flows naturally with little effort, but when we are in disharmony or division then life becomes a difficult task master.
So yes as you say if we chose to live in the shadow of a volcano because of the fertile land, then we might experience it exploding within our midst, the same as if we choose to live in flood plane because the minerals that the floods provide make fertile soil, then we should not be surprised when our home gets flooded, then next time the planet supplies us with the minerals that we so eagerly desire to grow our crops.
As you said in your post, people can change what you perceive as their karma, I perceive that everything begins and ends with a thought and our underlying thought patterns and beliefs creates or orchestrates our experiences upon this planet, so in this case, there are two things that can change, one is the location and the other is what you perceive as changing their karma and I perceive as transforming their underlying thought patterns and beliefs (core way of being) to create a new environment for them to reside in where they are.
Although we perceive and express things from a different perspective within our different understandings, at the end of the day, you say that what you perceive as their karma can be changed to accommodate the location, much the same as I perceive that their core way of being can be changed to accommodate the location, or they can move, we appear to have reached the same conclusion, so our thoughts are not that dissimilar.