Starting on a small chain of islands, with a continent to the south and a MASSIVE ocean to the north, this world is filled with islands, many of which are single-biome.
A large, deep ocean world I have been exploring, but have not yet begun to build. Although mostly ocean, savanna islands are in the north and snow forests and ice plains are in the south. (Seed: Seyda Neen, Large Biomes: On)