Emeralds and Villager Trading

So, according to 23W31A, Minecraft might update the librarian trading mechanics. Our current way of getting enchantments from librarians are in some ways, overpowered. You could get a mending book in the first 10 minutes. But having enchants set to specific biomes feels constraining. My solution: A) Redo the chances of enchants. Make more powerful enchantments like Mending or Efficiency V or Protection IV rarer than other weaker ones, like Thorns I, Lure I, or Protection II. B) Make emeralds more valuable. This could mean decreasing item amounts you obtain and/or increasing item amounts you must give in order to get emeralds. C) Make the emerald cap for enchants higher, so rarer enchantments can cost more than 64 emeralds. D) Do something about raids because raid farms are ridiculous.