Found a nice island seed - "Give me more islands!" (without quotes).
You start on a tiny island, and a ravine on a nearby island, and a 3rd island with a glitchy coast (you'll see - it's a random selection of stone, grass and sand in 1 chunk). Turning structures on gives it a tree and sugarcane. Turning structures off doesn't give you any.
You start on a tiny island, and a ravine on a nearby island, and a 3rd island with a glitchy coast (you'll see - it's a random selection of stone, grass and sand in 1 chunk). Turning structures on gives it a tree and sugarcane. Turning structures off doesn't give you any.