I support this but :
Some of the enemies are similar on what you see in other biomes and some had the same ability to the other ones.
Some items are also obtained in the Underworld,making it less useful in Pre-Hardmode. The location of the Biome can be changed,replacing it in the Ocean Biome won't be a good thing even I like the location. I suggest that it will be located in the middle of the Jungle or somewhere in the Underworld. This is amzing tho ! Hoping that Re-Logic will see this or even add this !