Make the deep dark harder

Right now, the deep dark has all the same mobs that the regular caves have. (zombies, creepers, skeletons, spiders) But since the deep dark is SUPPOSED to be harder, players should get a bit more challenge in the form of different mobs spawning down in the depths. The mobs above y0 don't really fit the deep dark's vibe either. Some suggestions for mobs I would like to see there are cave spiders replacing spiders, since they give the poison affect and make it harder to stay down there. Another would be witches replacing creepers, and not zombies, because creepers don't spawn as much as zombies, so you wouldn't be bombarded with witches, which are a very tough mob to deal with. Adding so many poison-giving mobs could also increase the value of honey, since milk isn't stackable, and you are already increasing the value of honey by adding candles and waxed copper, so doing this would extend that. I don't really mind how you do it, but I think the mobs under y0 should definitely be more challenging to deal with, you could add witches and cave spiders down there, and make a few new mobs too! I appreciate all the hard work and effort the devs go through to make each update perfect, and appreciate that they listen to the community as well. Thank you!