The step from 52 to 34 is out of spec for your front derailleur. It might work, but I wouldn't be surprised if it's rough. You could also replace the 52 with a 50, which would keep that step in spec. But switching from a 36 to a 34 doesn't give you much of a hill-climbing advantage.
I am also a fan of 46/30 chainrings. You would need new cranks for this (smaller rings need a smaller bolt-circle diameter). She could keep the cassette she has in back, get a 1:1 ratio low gear, and still have pretty close spacing between gears.