While I think that modularity can be a great thing, it doesn't mean that the girl, or boy for that matter, can have shoulders that look veeeery out of place. She seems to have either very wide shoulders, or has them dislodged. If you want to do modular sprites, I think that it actually does improve if you make separate sets for male and female parts.
I don't have an example here at the moment, but you can make modular arms with correct shoulders. Even in real life, arms don't fall straight down on women, they tend to fall a little bit on the diagonal side. RedSuinit's example is more anatomically correct than yours.
Another option you can take, is move the arms closer to the torso. You will have to adjust the shoulders as well to make it fit.
My edit on the right. I moved the arms a pixel closer to the torso, and edited the shoulders a bit to compensate.