In this case the minimum damage of the axe seems significantly lower. But i can not reproduce your crit multiplier ... if you got 1.5 for two-handed axes, then this must be item level based and not dependend on the blacksmithing skill level.
Right, now you are making me question my observations -- which is a good thing.
First person to have spare time and interest in this should make a thread for structured testing of weapon crafting in the help/tips/strategies subforum. I am way too lazy to do that (at least at the moment).