And does she intend to conceal or is she willing to open carry (in an area where it's legal)?

Nothing beats small guns when concealment is a premium. My go-to off-duty is a Sig P365. I'm a bigger guy (6'3", 250-ish) and it looks like the Noisy Cricket from MIB when I fire it, but I can carry it with virtually no printing in a variety of positions. So if that's the primary concern (the 2-legged predators) then yeah, I'd probably go that route.

There's lots of big guns you can carry on the hip if you're in critter country and looking for something to protect that way. As Bert mentioned there are lots of massive revolvers, and you could roll with something like a 10mm if you're interested in a semi-auto. Despite what I said about recoil management above though, those types of weapons are big enough that they can be intimidating and unpleasant to fire even to somewhat experienced shooters.

(Semi-Related storytime you can skip if you don't care: once upon a time the FBI got into a big shootout in Miami and decided their agents were significantly outgunned with their standard issue .38 Specials. They decided to try and adopt the 10mm round but discovered that the recoil and blast was having adverse effects on agents' marksmanship. They didn't want to spend the money necessary to train agents out of flinching, so they worked with Smith & Wesson to develop the .40S&W round, which was basically a 10mm with the casing chopped short to reduce recoil. So... Even the Bureau guys and gals wussed out about shooting the 10mm, haha. Take that for what you will.)