Could you add an API ability to get the main biome of an island. Would be handy since the biome at the centre is not always the main one.

I think this is a good idea! I can see where it could be useful, for example displaying the "main" biome of an island, or teleporting to the nearest island.

To implement this I think the com.github.hoqhuuep.islandcraft.api.IslandGenerator would have to be extended to add the method "getPrimaryBiome() -> Biome".

Thanks for raising this!