I like to use Hi Oleic Canola ($.04/ oz!) and Hi Oleic Safflower.
http://www.soapmakingforum.com/showpost.php?p=557367&postcount=9
I don't recommend using Soybean more than 10%, and add ROE .1% (or maximum recommended usage rate).
Favorite Lard Bar
Coconut 20%
Lard 50%
Hi Oleic Canola...