Target number shifting is another lever to play with, which is always good to have, both thematically and mechanically.

You want First Age Artifice to be impossible for Dragon-Blooded to make? Scale the Difficulty up and give Solars (who are supposed to be able to make First Age Artifacts) dice tricks and TN shifts so that their rolls can succeed, but Dragon-Blooded mathematically can't.

You want some Exalted, like Sidereals, to be able to reliably succeed at relatively easy tasks, but not at extremely difficult tasks? Target number manipulation does that. Meanwhile,...