My Mrs carries a S&W 1911PD, (Commander size) the slightly smaller size and scandium frame & Crimson Trace grips made it shootable for her. She had a Glock 22 at first and said it was "Too snappy z7 too heavy". She didn't like my 1911 Govt. and one day she and several lady co-workers went to the S&W facility out in western Ma. and she came home with the 1911 PD. These days, she's likely to grab my Colt Mustang when going out.
I'd suggest finding a range which has a good selection of rentals and buy her the gun she finds comfortable enough to carry and can shoot well.