Depending upon how severely she is lacking in hand strength, and what is causing it, you might be in a situation where either your wife NEEDS something like the EZ model, or she may be unable to shoot at all. I suffer from a severe case of rheumatoid arthritis. It is severe enough that when I have flare ups (which is frequently), I am forced to use a prescribed power wheelchair, and the strength in my hands/arms is so poor that I find myself unable to turn door knobs, button clothing, etc.
When my condition reached that point, I went from carrying and shooting whatever pistols I wanted to 100% of the time, to being completely unable to handle a pistol during flare ups. It was then that a friend mentioned the EZ models, and let me tell you that they are a tremendous blessing for those of us with disabilities. The pistols themselves are lightweight, the slides are easy to manipulate, the magazines are easy to load, and although they are a single action only pistol, they feel and operate similarly enough to a standard M&P that it’s easy to transition between them.
Granted, I still carry my M2.0 Compact every day when my body allows it as it is my preferred defensive pistol, and the one that I enjoy shooting more than any of my other handguns. But, without my .380 EZ, there would be a solid 30-40% of the time that I would be forced to go unarmed, and for me... that is unacceptable.
If your wife depends upon her firearm for defensive use, I would strongly recommend that you have her try out an EZ model. No matter how heavily invested you may be in her current handgun, it won’t help her if she cannot comfortably and confidently use it. Currently, the EZ models can be had for very reasonable prices. Just my dos pesos.