I'd have to go with Avatar: The Last Air Bender. Although I never watched this before, it would be nice to see one of those maps. No one really makes these type of maps. I don't like the name of a world named "Spirit world"...since of what is behind the meaning, but it's my opinion anyway. Besides, a Warrior Cat map is too basic and mainstream - with the woodland and such in there. There are some maps with a bit of a Warrior Cat theme. As for the Land of Ooo, I think it would be too much work and might slow down your computer/laptop and take up a lot of space in its memory. Overall, I guess The Last Air Bender is the right choice, including that you have already started it.
Otherwise, I wish you luck on carrying out this project.