Most subcompacts have double action only (DAO) triggers, with long and relatively heavy pulls. The Nano, PF-9, CM9/PM9, LC9, LCP, and P3AT all fall into this category. These extremely small and light pistols tend to be snappy, and difficult to shoot with. Exceptions are the Shield and the Walther PPS. The Shield has a shorter pull than most subs, and the DAO of the PPS is said to be smoother than many competitors.
My girlfriend hated my PF-9 and LC9. She surprised me, and decided that she wants a Ruger LCR .38 spl. A serious consideration is how your lady will feel about her pistol. If she loves it, she will want to practice more, and will become more proficient. As long as the weapon she falls in love with is reliable, I suggest going with that.
As for you...
You refer to the FNS too frequently to buy anything else! It's a solid choice, and you obviously want one!
Currently Own: Beretta PX4 9mm, Glock 23 (Gen 4), Glock 19 (Gen 4) x2