Well, you hit the right sites with Cornered Cat and Falia Photography’s Youtube videos; my wife really learned a lot from them. For my wife’s deep concealment, she has a Kel-Tec P3AT .380; it’s small enough to wear in a bra-holster under the arm with a tight T-shirt or a small custom (I think it’s a Crossbreed) holster for the small of her back.
She also has a Bersa .380 which she still loves and uses the most and more recently she’s been enjoying a Ruger SR9c. The SR9c is almost as big as the Glock 19, but a tad slimmer in profile. I’m thinking on picking up a Kahr PM9 or CM9 for myself and letting her try it out.
Women’s clothing can be hard to dress around a gun, but my wife has really took it on as a challenge. She’s been buying light-weight casual-dress vests that drape over her shirts or even dresses. She’s tried ankle holsters, shoulder holsters (both are good for driving longer distances), Inside and Outside waistband holsters, etc. She has probably a good dozen holsters for her pistols. She also wants to try a garter holster for when we attend more formal dress events, but her favorite holsters are by Crossbreed. She’s found instead of carrying on hip, she has it more stationed in the small of the back due to the more tight fitting clothes. She really like the shoulder holster when traveling, but would rather carry inside her waistband if at all possible which is also what she practices with at the range the most.
I myself ended up carrying my Glock 26 over my Glock 19 for most of my summer-weather carry. During the winter when I can wear a jacket, I’ll pack a larger pistol.
Once you find out which carry systems are best for your choice of dress, make sure you practice drawing at the range with them. That little “bra” holster conceals extremely well, but my wife has to practically expose her chest to draw quickly and engage
…I made sure to have her practice that over, and over, and over again
…fortunately we were on a pretty isolated range, so I was the only one enjoying the practice
Good luck and please follow up if you select a new gun and holster system; there are a lot of women who could benefit from other women's experiences.