The reality is that rods have slimmed down due to modern technology. Even the price pointed rods are as light as many premium rods from years ago. That mushy 8ish foot 5 weight Wally World rig that your wife is using has graphite technology that is ten or more years old.
As for actions and lengths, there are three criteria to make her choices off of.
- Water types. Big water, small streams, both?
- What kinds of payloads will she be throwing? Dries, indo-float-a-bob-cators with split shot and multiple nymphs, streamers with heavy sinktips.
- What kind of action does she prefer?
If I was going to play the statistics based off of past observations, here are some choices that are popular in the western states with women.
- Small to medium streams, mostly dries, light nymphs and streamers. 8.5' 4 weight medium fast action.
- Medium to big water, a mix of everything, 9.0' 5 weight medium fast action.
- Big water, a mix of everything but favoring larger flies, usage of heavy sink tips for streamers, 9.0' 6 weight fast action.
I won't talk rods brands and models. There are a lot of good ones at every price point thanks to the trickle down of technology.