If we must change the $10 bill...

 

Although I don't condone replacing Alexander Hamilton on the $10 bill--he was a financial genius who's astute example Americans desperately need today.  But if the criteria for replacing his image is it must be woman, I nominate Madam C. J. Walker, for she, like him, knew economics inside and out.   Also like Hamilton, she succeeded despite seemingly insurmountable odds. She became the wealthiest businesswoman in the USA, circa 1919 when she died, at age 51.  She actively taught other women how to succeed in the business, too.

http://www.edwardianpromenade.com/women/fascinating-women-madam-c-j-walker/