My family and I did the Wild by Design tour a few years ago. We enjoyed it very much. The tour began early in the morning, prior to official park opening. It was nice because you're "connected" to the tour guide via headsets, so you can easily hear the tour guide, even if you're at the back of the pack.
Essentially, the tour will give you an insider's view of building design, the desire of Disney to ensure that structures were as authentic as you would find in Africa, Asia, etc., "theming" stories, etc. We learned interesting facts about some of the animals, their feeding habits, play habits, etc. It was also very interesting to hear how Disney ensures that the animals are well taken care of in every respect.
The outcome for me -- and the guide stressed this during the tour -- was "slow down and enjoy." Most people race right through a lot of the park, just to get to a ride. There's a great deal at Animal Kingdom for one to take in, if you just take the time to do so.
Debbie