Really difficult choice between the River and Jungle biomes. I love the music and atmosphere in both, but given all the over-crowding along the river, I voted for the Jungle instead.
That said, the purges in the jungle really need some work to make investing in the area feel rewarding. Getting nothing but snakes and lizards when there are 2 human factions with a presence in the region is disencouraging in the extreme. As a result, even though Jungle is my favorite biome, I’m obliged to spend most of my time in the savanna and desert instead.