I'm not sure what enemies they'd add to an infected jungle, though that's not to say it's a bad idea. Maybe enemies that are much more disease-based, hostile and exotic for the corruption, crimson and hallow respectively.
I just want something to turn grass and dirt into jungle grass and mud, like a lime solution that turns dirt into mud and grass into jungle grass. I'd even take a powder made from some kind of new jungle mushroom.
If you break down the most iconic ones you have: flying enemies that inflict poison, wall crawling enemies, and tortoises. Then you can split these across three jungle alter egos:
sinister swamp,
bloody bog, and
rainbow rainforest. I once made a few ideas (that I really love sharing).
Hornet variants: Plague Crows (slow, powerful feather projectiles that inflict poison),
Malaria Mosquitos (shoots very weak, poisonous, ichor-like streams of red blood that are hard to dodge),
Starfruit Bats (spits average damage poisonous seeds like a machine gun).
Jungle Creeper variants:
Corrupt Centipedes (worm-AI, can climb along walls, drop rotten chunks),
Bonerantulas (basically an upgraded Creeper, also a Zelda reference, drop vertebrae),
Glowtail Geckos (positions itself in range and launches confusion inflicting tails).
Tortoise variants: Cursed Snappers (start slow but get more vicious as they approach death, inflict and drop cursed flames),
Ichor Boneplates (can periodically crumble into a pile of bones as a defensive technique, inflict and drop Ichor),
Crystal Softshells (release close range fragments of crystal mid-flight, inflicts bleeding and drops crystal shards.
I mean, yeah, all they really need to do is make different grass types able to grow on mud, but this would be so awesome!