The problems with women's belt holsters come from two main factors:
1. The curve of a woman's hips often tilt the grip into the body, making it harder to draw the pistol.
2. Women's clothes are often "high waisted". This also impedes the draw.
Of course, women's figures vary, as do men's, but for a woman with these problems IMHO the best belt cary is in the "appendix position" forward of the point of the hip bone. This literally puts the pistol "ahead of the curve" if you'll pardon the pun. Problem is, the further forward you wear your sidearm, the harder it is to conceal, but it's possible to choose good concealment garments from the wide range of women's fashions. A peasant blouse or tunic top works if you practice the "Hackathorn rip" (lift garment with left hand, draw with right).
Ken Null's "Gibson" is supposed to be a good appendix holster. A Belly Band would also work this way.