If your wife found the ppk uncomfortable to shoot, she will hate the Ruger sub compacts.
Having owned many .380s over the years, including from PPKs, P232s, KelTec P3ATs, and a PK380 among others, I would recommend the Sig P232. It's a fine pistol, accurate and very comfortable to shoot. The trigger pull in SA is around 4-5lbs factory. The P232 is IMHO a much more comfortable shooter than the PPK in .380 acp, although I do love my PPKs. Has your wife tried a Makarov pistol, E. German or Bulgarian not CZ82? They are similar in dimension and operation to the Walther PP and also fine shooters, much less expensive as well.
BTW, if she really likes the way the ppk handles and shoots, consider putting on a Hogue grip sleeve. They really make a comfort difference on the PPK. I have one one my range shooter PPK.
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