The best advice may be to take her to a range where she can try out different guns for herself and let her decide. I tried the "I know better what you need" route at first with my wife and wound up spending a bunch of money on guns she didn't like.
HK's in general, and P30's specifically, come from the factory with very stiff recoil springs. They are manufactured to NATO specs and tend to do better with the more stout ammo to start off life. I have not had an issue with any of my HK's as far as brand, but I would suggest running your P30...