Is there a way to remove granite biomes, shadow orbs/crimson hearts, marble biomes, the underworld, spider biomes and oceans from the world. It's not a real skyblock experience for me if there's random patches of biomes scattered around everywhere, most biomes like the ocean do not add any normally unobtainable blocks.
There could be a recipe for marble and granite blocks
adding spider walls but not the biome allows for web farming while still keeping the world void
ocean and underworld too are unneccesary, I could create the ocean myself if I wanted too, though hellstone and the hell forge may be an issue but there's always a solution that may involve crafting or vendors.
eater of worlds and brain of chtulu can be spawned by using crafted spawners and the drops from the hearts/orbs can be obtained by fishing
The dungeon and temple are kinda a big deal and I can live with them in the world but there could be a replacement. But you could place a small stretch of dungeon wall somewhere with a bit of dungeon bricks with the 4 chests on them allowing you to build a farm and later get the chests. (locked chest drops can be obtained by fishing nearby), if needed you could add a dungeon wall recipe that uses bones for the people that like building. For the temple you could add a small box somewhere with a locked temple door with a golem altar inside and some backgrounds so you can farm there too, golem drops could be used to craft temple walls and from those you can craft temple traps.