I totally agree with the trip suggestion. Plan every detail, showing that you thought of her at each stage. You could even make it low-cost in certain aspects, like taking her on a fantastic hiking trip she's never done, and packing a lunch with all of her favorite foods.
The fun thing about women is that there are certain items that we could own 100 of and still not have enough–– things like clothing accessories (or kitchen gadgets!) come to mind. Do you live where it gets cold in the winter? I personally love socks, and can never have enough fun pairs, especially wool socks. You could even incorporate small gifts as part of the hiking trip if you decide to take the hike. Along the trip, when you stop for a breather or a water break, take out a small gift, like new socks, a very effeminate scarf, small jewelry, a personalized coffee or tea mug if she's a hot beverage drinker and surprise her.
Excuse my gushing, but I love the way you talk about your wife, and I hope you have a wonderful time together, regardless of what you decide to do. She's lovely!