Where to next?

We've been back from our vacation for a couple weeks. It was our first real vacation since Dec. 2004. Recently, I've been thinking about my long term travel plans. I have this idea that I will hit all the major countries of the world, plus a bunch of smaller ones. I have an amorphous priority list of where I want to go. I also have a couple different categories of destination.

In my mind, there are major once-in-a-lifetime destinations. These would be places like China, Egypt, Kenya, etc. They are so totally different from my daily life that they represent a unique experience. Usually, they represent a significant amount of travel time, and consequently, a significant financial investment. Destinations in this category require a trip duration of no less than 2 weeks, preferably 3.

The next category of destination is more common. Places in this category typically represent a significant cultural or historic value. Italy, Japan, and Spain are examples. I want to go to these places, but they aren't my dream destinations. I could go to them without fear that they will be unreachable in the future. I would still want to spend 1-2 weeks in a given place, but places like Paris or London could be covered in a long weekend. One hindrance to choosing one of these destinations is that my wife has already been to many of the places I would consider my top choices. While she would always accept a vacation, I'm sure she would prefer to go someplace new instead of someplace she lived for years.

The last category is the generic destinations. This covers places that I would like to go for one reason or another, but I could just a easily go tomorrow as I could 20 years from now. Most of these destinations consist of states in the continental US, the Caribbean, Canada and Mexico. Some could be longer trips, but most could be covered in a week or a long weekend.

So, right now, my top destination choices are:
Category 1: Kenya, Australia, and Greece.
Category 2: Spain, Paris, and Italy
Category 3: Grand Canyon, Alaska, Florida, Northern California and St. Lucia

So, which would you choose? I'm thinking Florida would make a nice Sat. - Sat. vacation next Christmas. The kids would be a perfect age for the theme parks and my wife likes to go someplace warm. I also think we might try to do a mommy-daddy weekend in Paris sometime when we find cheap airfare, but I'm not too keen on the French based on my personal experiences. I think Greece will be the next big vacation, but given past experience, that won't be until 2016-2017.