Right now, there are not much plant species in this planet. To be a more exotic, beautiful and natural planet. It needs more diverse plant species. The species can be designed taking in to account of biomes, terrain and environment. The species should fit in with the environment. Please name them too. Nice name :)

More diverse and exotic terrain and biomes which should blend together to create a single world with diversity. Right now, there aren't much of diverse biomes and terrain. The biomes need to be unique to Earth (game's default world). The biomes can have different plants, terrain and climate. Also, the biomes and terrain can be designed somewhat according to nature and environment. They can be fancy and bizarre (because this isn't Earth). But I think, it is really nice to have them built based on principles of nature. I know that fantasy doesn't really go along with reality. But the aim here is to create a sustainable, beautiful, exotic and natural planet. I think that taking in to account the principles of nature can help achieve a natural world. Use your imagination. -- They don't have to be ultra-realistic though. -- It's an exoplanet "TS-180812R".

Was doing some testing and had a single chunk break due to a ConcurrentModificationException - looks like there might be some poor map handling around ExoplanetFloraRasterizer:86 - being that chunk gen is multithreaded this could happen, yet even without multiple threads maps can be sensitive when messed with during iteration.

Involved code snippet in method getRandomFlora:

        if (!flora.isEmpty()) {
            float rand = random.nextFloat(0, 1);
            float cumulativeProbability = 0.0f;

            for (Map.Entry<Block, Float> entry : flora.entrySet()) {
                cumulativeProbability += entry.getValue();
                if (rand <= cumulativeProbability) {
                    return entry.getKey();
                }
            }
        }

Error snippet:

ConcurrentModificationException: null
	at java.util.HashMap$HashIterator.nextNode(HashMap.java:1437)
	at java.util.HashMap$EntryIterator.next(HashMap.java:1471)
	at java.util.HashMap$EntryIterator.next(HashMap.java:1469)
	at org.terasology.exoplanet.generator.rasterizers.ExoplanetFloraRasterizer.getRandomFlora(ExoplanetFloraRasterizer.java:86)
	at org.terasology.exoplanet.generator.rasterizers.ExoplanetFloraRasterizer.generateChunk(ExoplanetFloraRasterizer.java:66)
	at org.terasology.world.generation.WorldImpl.rasterizeChunk(WorldImpl.java:64)
	at org.terasology.world.generation.BaseFacetedWorldGenerator.createChunk(BaseFacetedWorldGenerator.java:75)
	at org.terasology.world.chunks.localChunkProvider.LocalChunkProvider$1.run(LocalChunkProvider.java:653)
	at org.terasology.utilities.concurrency.TaskProcessor.run(TaskProcessor.java:50)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:745)

Otherwise the world still seems to work well, including the portal to get there. Not sure why this was never added to the stable module lineup, must have been missed, so I'm adding it now. Belated nice work @PutawanDE ! :-)

Right now, the plants are generated according to flora density and tree density, hard coded in each biome. Each biome has temperature and humidity properties which are not being used. It would be nice to have temperature and humidity determine the tree and flora density. Also, different plants can have different density which vary in different biomes.