For two carry systems, I would also recommend a small fanny pack as well. Lots of options, but the smaller, the better just for ease of carrying. Easy to grab and put on in any (or no) attire, can be covered up by a hoodie, and off-body carry is less of a concern in/around the house.
Outside the home CCW with loose fitting clothes and likely not wearing a steel-banded gun belt, PHLster Enigma is going to be one of the best, purpose-built options. Expensive to get into, but vastly superior to most other on-body, non-belt type pants, and excellent concealment while maximizing comfort. The challenge would is getting your wife to agree on trying it out for a month or two.
Bra holsters. My wife went overboard in the CCW world about a decade ago. Did a lot of research tried various carry methods, etc. She only carries her diminutive Kel-Tech P3AT .380 when she was backpacking solo. She uses a Ruger SR9-compact for home defense (bedside gun and primary training handgun), and her LC9s is really what she prefers to CCW. She found that a light dress vest, tunic-like garment would work perfectly without having to change her entire wardrobe or attire choices when carry concealed.
She did get the "Flash Bang" bra holster and practiced it on an empty range (depending on how vigorous your clear and draw is, you may very well flash the target

). Word of caution for you men. First, that's a great place for concealed carry despite the one cautionary concern. The holster connection to the bra really tore the bra up and if your wife prefers certain bras for fit and comfort, you'll be surprised at what a quality bra costs

! just a cautionary warning.
ROCK6