Olaudah Equiano and Mary Seacole would be the classic nonwhite choices, especially considering we've had William Wilberforce and Florence Nightingale on banknot

Olaudah Equiano and Mary Seacole would be the classic nonwhite choices, especially considering we've had William Wilberforce and Florence Nightingale on banknotes for related achievements. I guess having Gandhi cancels out his longstanding critic Churchill...