1.18 Generation Suggestion

I recently watched my friend play the new 1.18 Experimental Snapshot, and I have some suggestions.

1. New mountains are overabundant, making regular plains and biomes extremely rare.

2. Try to optimize the performance, the new snapshot had some serious performance issues. My friend can run at 110+ in 1.17.1, in 1.18 they get between 60-30 fps. 

3. Make cave biomes less rare, the only new cave biome we saw was a Dripstone Cave after a 30 minutes search. We tried different seeds aswell.

Thank you and have a nice day.