I honestly agree with noscoper. Biomes appears way too often. I even have images where boards are just filled with biomes, there was no other map to select. It may be randomized in how the maps are picked/placed, but it doesn't really work out. You still see Biomes 90% of the time. My friends also have images of this happening. Besides, every time I see a biomes, it never fills up. They are always empty. Despite that not many players like this map, it causes lag. I tried playing this map once and I would freeze every minute. It produces lag and I don't really see any advantage in having Biomes as an option when other people enjoy other maps a whole lot more.
People even created a hashtag - #ACubeCraftWithoutBiomes. That's what I usually see when I go into lobbies.