My recoil-sensitive wife started out with a Benelli Nova Youth in 20 ga. It's light, and the stock fits her. Unfortunately, it wasn't but a couple rounds of trap and borrowing a 12 ga 11-87 and she'd "outgrown" it and wanted a 12 for herself.

Her 12 ga 11-87's stock has been cut down to fit her, and the Nova's been in the safe ever since. One day, it'll come back out when the youngest is ready to start shooting.

She didn't find the recoil of the 20 ga much different than that of the 12. The auto certainly reduces some of it, but she's since used one of my 870s as well, and didn't find it objectionable other than the stock being too long for her. Knowing what I do now, I'd probably have been better off just starting her out with the 12 ga auto.