The first 2 his 14 reasons:

So, on to what makes Naboo appealing...

1) Diversity of Terrain. Of all the Star Wars planets, Naboo is one of the most varied in terms of terrain and environments. We can include swamps, rolling hills, cities, underwater environs, even snow-capped mountains (which appeared in LucasArts´ Battle for Naboo). We´ve started with the environments seen in the film (specifically grasslands, swamp, Theed). I put "diversity of terrain" as the #1 factor in selecting Naboo because it was also our #1 reason for making it the test planet - we knew that if we could make all the varied terrain on Naboo work and look right, the other planets would be much easier.

2) Diversity of Animal Life. The creatures on Naboo are just as varied and exciting as the terrain itself. From the dangerous sando aqua monster to the docile shaak, Naboo is rich in animals...