We need a choice for "Listen to your wife."
I agree with spartan. Just because she doesn't agree, it doesn't mean she's against you. In this instance she's really just acting as the voice of reason. All grain brewing doesn't require a complicated setup, and I would recommend making a few beers before jumping into building. My reason, is that your setup might change because you prefer to do things different from what you have seen. I've seen a ton of different setups on this site as well as other places. Just because you have the mindset for a certain system, it doesn't mean it's the best for you. Spending less money up front will save you more money in the long run when you are doing less backpedaling.
On a side note, having the experience in all grain will make you better informed in presenting a solid argument to the wife.