Soy wax is a good wax. I personally don't use it but if that is what you want to use go for it. There are some FOs that do not wax as well in soy as they do in other waxes so you just have to test them out.
I have heard a little beeswax can slow burn time down in paraffin so it might work in soy. And yes, the standard it 1 oz for pound of wax but again test, test, and then test.