Well, first off do you have fast passes and which rides are they for? Are you traveling with children or adults only? After that you have to decide the shows your family wants to see, I would not miss Festival of the Lion King, also if you have children Finding Nemo is also pretty amazing to watch, I typically do 2 AK days I have 2 children. We do a show each day and then spread out the rides, they also have a bone yard play area that my kids spend an hour each day at as well, its a play ground where they can hear dinos , dig for them, and play with other children, with that in mind if you want to do Avitar I would say 2 days if you DONT have a FP for it, the line will be a while, Have a great Trip