considered others?
First: Have a look at "cornered cat" 's website. Just google "cornered cat" She's a moderator on here and has an entertaining, knowledgable website that may (or may not) be designed for a woman, but is lots of fun and illustrated enough for a man
which definitely covers the "which pistol" question that plagues us.
Second, now the industry is currently in the CRAZE for smaller concealed pistols. Back in AMT's prime, steel was still the big thing. Now polymer, aluminum or a mix of those with steel is in and although many still don't like it, its lighter, cheaper, has held up to use depending on the firearm, and is 1 less thing to rust or worry about. Doesn't look pretty though
Now there are single action, striker fired, pre-cocked double action, as well as true double action only on the pocket pistol market to be had. Also most are lighter than all steel AMT's.
Just a few small guns that come to mind
Single action: Colt 938, Kimber Solo
Striker: Ruger LC9s, M&PShield (a little larger than pocket pistol), XDS
Pre-cocked Double action - tends to be lighter than true double action - Kahr CM40 or CM9, Ruger LC9. S&W Bodyguard 380, Ruger LCP
Double Action - Ruger LCR (a revolver famous for it's lighter pull) in 38 special or 357.
I'm sure there are others. For an all steel 40 cal pocket pistol, Kahr MK 40 however it would be more expensive than the polymer Kahr 40 calibers.
If your mind is set on double action - or something very similar (pre-cocked double action) I have and recommend trying the trigger pull on a Kahr CM series pistol. They do make a 40 caliber version. I have the 9mm and its a very smooth pull, and since it's pre-cocked the pull is notably lighter than a snubby revolver. Aftermarket striker springs can be had to make it an even lighter trigger pull but I opted out. Make sure she can forcefully retract the slide since you'll need to do that to load it. Usually it's a training issue if folks find it difficult. I've brought a snap cap the gun store and asked if I could try the trigger pull just once on a firearm I wanted to handle. They get less antsy that way.