Jacquie,
First off, Tinkerbell. Now they have a permanent greeting place for her, called Pixie Hollow in the Magic Kingdom. It is not just great knowing that she will be there, but the experience is great too, with how they have decorated the area. It is like you are shrinking to her size as you go to meet her!
For princesses, I still think that
Restaurant Akershus in Epcot is the best way to meet as many as possible. It is a great meal too!
Finally to your question about the Water Parks and more option. Personally, I don't get it. My kids find the resort pools to be more than enough water time, and we never go to DisneyQuest or play golf. I prefer to save my money for other things. Unless you are big water park enthusiasts, I would suggest you do the same!
I am glad to answer any follow-up questions!
Have a magical vacation!