Items Various suggestions (because I like skyblock challenges)

[Vasxus]

-Hellstone needs to have some renewable source. Currently, it's locked to being mined in hell. Just make it available in obsidian/hellstone crates and the zenith is renewable.

-The Hellforge has a similar issue. 10 hellstone ore and a furnace at an anvil should be alright. This frees up all hardmode ores between adamantite and chlorophyte.

-There needs to be a way to get the lizarhd altar without just having one per world. Craftable with power cells and chlorophyte at adamantite forge. solved.

 

[Asternove]

You have to lock the altar until post-Golem. Make it out of Lihzahrd Bricks and Power Cells instead.

Speaking of which, I think those could be made by shimmering Martian Plating, making them renewable.