I really like the concept of there being an official boss to the Hallow much like every other special biome, but I'm just not so sure about it being a knock-off of the Eater of Worlds. :\ I don't want to offend you or anything but it won't represent the Hallow being a spreading, special biome on how it's intended to be instead of another version of the Corruption. Each spreading biome, and the jungle, has it's own unique boss. The Crimson has a totally different boss then the Corruption, and vice versa. It's not a recolor of the EoW, it's a brain, a totally different enemy with different ways to kill it. Although, there is the Destroyer, there is no official biome for it to represent for its a mechanical boss. 2 worm bosses are fine, but 3's too many. :\
I still love you
I'll support but doubt it'll get into the game.