Re: What's the source of the problem when one foot is turned out a little?
You may also want to consider seeing a chiropractor. A good one should be able to recognize postural asymmetries (something you have already done), identify the source/cause of the asymmetry, and with treatment, help to correct it. If for some reason the chiro is unable to correct the problem, a good one, should be able to refer you to someone with a different specialization that can help you. I have one leg that is slightly shorter than the other, which had caused all sorts of chaos in my alignment, but with the help of my CrossFit coach and my chiro, things seem to be evening out.