Current version of the mod has issues atm with iridium acquisition (which is being remedied) and profanum acquisition. This could be fixed by taking some inspiration from alltheores approach: generating large batches of them with a raw ore block/block of the ore in the center. (Obviously rare to match the yield)
As for the expansions, some examples of new generation that could be cool:
Profanum: for an ore so hot that it literally burns you, why not have it generate in the nether exclusively? This could generate at the floors of lava lakes/shores of lava lakes in batches as to ensure a fair amount while still maintaining the same rarity/scarcity.
(Bonus mini suggestion for lava vision if this idea is accepted since current lava fog is very annoying)
Iridim imo doesn't need changing, the batches/clusters alone would remedy the demand on top of new method
Supermassive gem veins: similar to how copper and iron have super veins with granite and Tuff. The gemstones of onyx, sapphire, ruby, topaz, and Iridescent gems could feature their own variant with a matching block to the vein to recognize it
Sapphire -> Diorite
Ruby -> ignostone
Topaz -> andesite
Onyx -> stellar remnant
Iridescent Gems -> amethyst (could also spawn ores in special amethyst clusters)
Which seaways into Stellar Remnants ->
Instead of randomly spread, they could be confined to superveins like the tuff/granite. On top of 2 mini structures, floating stars and crashed stars. And where there's stellar remnants, there's onyx ore. Would be mostly made of stellar remnants/endstone, and add some cool details to the end

