I thought it might be illuminative to look at some female pirates and try to determine how successful they were. Then I stumbled upon this, and decided to give up the search.
Cheng I Sao (Ching Yih Saou) — 1810s, South China Sea, commanded either five or six squadrons consisting of 800 large junks, about 1,000 smaller vessels, and between 70,000 and 80,000 men and womenNo doubt, she was a pirate fo the first rank. I bet she made the British navy soil themselves.
For more on female pirates, go here.