I say it is not min-maxing. If you were min-maxing, I think you would have arranged your stats as follows:
str 14
dex 18 (21)
con 17 (16)
int 12 (11)
wis 16
cha 15 (14)
Then taken the weapon focus (rapier), weapon finesse (rapier), and improved critical (rapier) feats. Next...