Good choice with the SR9cSomeone else asked the question, and I'll repeat it-- Who is driving this? You or your wife? What does SHE want? Your statement, "I think I'd like to get an auto" tells me your wife is probably doomed to get a gun she won't like or won't shoot. If it's her gun, it should be her choice. A gun is a very personal thing. Many factors go into it. Her hand size & strength, her experience with guns, her reason for wanting a gun, how she'll want to carry, etc. There have been many threads like this here, and there is a sticky that addresses this here:
https://www.indianagunowners.com/forums/women_and_firearms/12684-buying_a_gun_for_the_women_in_your_life.html
For what it's worth, which should be very little, my husband bought me a Ruger LCP .380 as an EDC, which I struggled with, as it was NOT a great first gun. If we had discussed it more and I had tried out some guns, I am fairly sure I'd have ended up with a Ruger SR9c, which will likely be my next purchase.
The short answer is, it doesn't really matter what anyone says here. Take her to some gun shops, let her handle some guns, get some answers to her own questions. Take her to a range where she can shoot a variety of guns and then ask her what she wants. Then you'll know what gun to buy.