“Best” can be taken in various ways : the most heroic, the one who change the most how people perceive her, the most endearing, …

But if you had to choose only one who will it be and why ? A recent one (Hermione Granger, …) or an older one whose name is still known today and proves that she has marked the spirits? (Scarlett O’Hara , Jane Eyre, Lady McBeth, …)

I’ll go for Artemis one of the most widely venerated of the Ancient Greek deities and a nice mix between feminity and strenght.
Her name is use since ages and is still relevant today (Percy Jackson, …)