I’m a little confused about your wife’s needs because she started with an ‘event’ requirement and also said she wanted a basket. So I’ll offer general categories and things to think about to help with the decision.
Gone are the days of simple bike choices like road or mountain. But that’s good for us but sometimes hard to decide between categories.
From reading the posts (sorry if I missed any details) it sounds like a hybrid would be good. Hybrids generally have a road friendly geometry resulting in spirited performance. Fast but not rocket ships. On the other hand, the basket comment has me wondering. You could try mounting a front basket or run a rear rack with grocery panniers or basket(s). Mounting front baskets can be challenging due to cables, shifter, etc. in the way.
Also look into the ‘commuter’ bike category. Generally they are spirited, comfortable, and reliable because they have to be.
If she’s riding more than 10 miles pretty regularly, consider drop bars. Getting into the drops in headwinds makes a huge difference. Generally drop bars require a bit more flexibility. However, if you review touring riding positions, you’ll note that they can be configured to be pretty upright and comfortable.
That leads me to bike fitting. Bike fitting is a great idea especially if you are uncomfortable. Find a bike fitter that is also a PT. They can correlate your physical abilities and/or limitations to your bike. They’ll direct you how to improve fitness and fit your bike to you for maximum comfort.
Look for a steel of aluminum frame. Steel is more comfortable, aluminum is lighter. Look for braze-ons for front and rear fenders or racks. Fenders are only a pain if they are the strap on type used when you don’t have braze-ons.
Schimano Tiagra is the minimum ‘good’ IMHO. I commute on it. It’s solid. I don’t recommend anything below it unless you need to go below for budget reasons. You don’t likely need 105. They are nice but expensive. My road bike has Ultegra Di2 and the mountain bike has Deore XT. Way too much for her.
For age. I’m 41 and commute 4,500 miles per year to work year round not including mountain biking and road riding. I’ve ridden with 65 year olds that can tear my legs off. I’ve dropped 25 year olds. It does not matter. Fitness including strength, cardio and flexibly matter.
Agree with comments about finding a good bike shop. They’ll be able to ask you lots of questions and direct you to the right bike.
