I also have the girly arches and ankles. My feet are completely flat, I almost have an inverted arch. I haven't tried to go with the minimalist shoes, but for everyday use, I try to use less shoe to help strengthen the arches and ankles. In the mountains I pretty much need the support. I look for higher boots, but not super stiff because I have had the slip problems, too. Going downhill, loaded, and on loose scree material is where the extra support really seems to help me. I will have to work on the right sock, insert, etc.combination, that is some good advise. I agree also that the right fit for your feet is important. I have had some trouble with work boots that were spendy but not right for my feet lately.