I was talking about regenerating ores, not generating weird pseudo ores. I don't really understand how these pseudo ores would work. For example let say that you want to add redpower to the world that didn't have it before. So if you wan't to just replace block ids, you would have to have block with 7 different metadata types generating with on very different levels with different cluster size and frequencies. Some mods also add more complicated generation. Railcraft saltpeter generates in hot arid biomes with sand and sulfur generates in extreme hills near lava lakes. So practically you would have to replace those pregenerated pseudoores with different blocks, it really isn't that much different then just generating in smoothstone, except that it would make it a lot more complicated.