While a very good idea, this may lead to an impossible to strike balance as some character keys will give an advantage while others may slightly nerf a player. Consider the case of a character requiring more of a very rare material to achieve a similar result to your ultimate amps recipe ... maybe an additional 2 pieces of a specific sup amber ... then that character would be at a disadvantage hard to properly compensate.
If you only have a small set of equivalence classes, it's possible to balance by giving advantages in other recipes, but then it's going to be easy to reverse-engineer by checking the results on a simple basic recipe.
If, however, it's each character key in its own class, statistically half of the server will be mad as hell :)
Plus all oldies who have a stuffed recipe book may feel cheated out of their finds/acquisitions as they now need to tune each recipe to their key.
If you only have a small set of equivalence classes, it's possible to balance by giving advantages in other recipes, but then it's going to be easy to reverse-engineer by checking the results on a simple basic recipe.
If, however, it's each character key in its own class, statistically half of the server will be mad as hell :)
Plus all oldies who have a stuffed recipe book may feel cheated out of their finds/acquisitions as they now need to tune each recipe to their key.
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