In my opinion make the character a strong character who happens to be a woman. its one of the big mistakes that gets made making a strong gay or black or woman character instead of strong character
the writer ends up making the defining trait the characters femininity or gayness or blackness and the character has no other characterization beyond that
lets use Sakura as example before her character assassination
as plot points for the character she had the following
A: Step out of Inos shadow and stand on her own
B: become a strong kunoichi never give up
C: be able to stand in front of her teammates instead of behind them "watch my back now"
D: find love
each of these plot points is and can be seperated from naruto and Sasuke in some way so that if you remove them from the equation the plot point it self still stands by itself as a breathing point from which the story teller can work forward from and which helps define the character without her love interests as a standalone character in and of herself
A: she wants to be stronger so she can stand on her own
B: She has a never give up attitude and a will to win
C: Stand and protect others instead of being protected
D: find someone who will love her for herself and her flaws
again as you see not once are the two male leads mentioned in her motivations though in the story theyre the core. But as you can also see that removing them from the motivations doesnt diminish them in the slightest
While Sakura can be rescued from a bad situaton here and there she is still fully capable of handling herself and standing on her own as a character with her own stories and plot points
Sakura is a strong character by herself to a point where she stands on her own as part of the story
Karrin Murphy is another example as well with her own plot points and troubles which she overcomes during the course of the dresden files shes no mere love interest, She fights and gets hurt and even needs to be saved on a couple of occasions, but that doesnt means shes weak no sir, she comes roaring right back and takes on bad guys way out of her weight class sometimes quite literally
Karrins character arc is clearly defined throughout the series and again we see how if you remove harry from the story you can see how Karrin stands on her own as a character without him, How a Karriin murphy files would function with her as the protagonist with out stretching any of the story basics or world building to accomodate her
Strong characters stand on their own in the sense of not needing another character to validate their existence in the story. Sakura does NOT need Naruto or Sasuke she has her own plot elements that with very little effort can be modified to support her as a standalone
Same wth Karrin
the key takeaway is to make sure when making a strong female character that you first make a STRONG CHARACTER who happens to be female. let it be a trait but not let it be the sole trait that defines the character above all else