Sounds kind of selfish to make her get what you want. But maybe you aren't. Just seems from the posts that your wants are the overriding concern.

My wife won't even look at a bike with 700C wheels anymore after having a very small framed bike with 700C wheels. It just didn't fit her short 5' 2" height like she wanted. So if those wheels you want to put on your wife's bike are 700C, then you might find she won't ride much.

But if your wife has always been a very active person she may not mind the bigger wheeled bikes.