I don't think we'll ever have a female black ranger as they don't tend to give the girls stereotypically masculine colors. Blue/Yellow tends to switch off on the male/female every few years. I think it's possible to have a green, though kinda unlikely.
Quote: "When I first started, I knew everything about nothing and have progressed in the subsequent two decades, realising that now I know practically nothing about everything"
Personally, I don't really care what colours go with what genders. I don't think they'll have a black female member just because it's easier to market that colour to boys.