Since the core concept of the Sturdy shaders is making color expression dependent on light position, rotation and intensity — not to mention the viewpoint chosen by the user, — in this timeline color expression will remain a little bit untameable. That’s the whole point of it.

That said, there are at least three ways of nudging color and hue expression within the Sturdy node group.

The fastest one is right on the top of the adjustments stack: it’s the Accent Color. Changing the Accent Color will nudge the brush strokes magic into your desired direction, while keeping color expression determined by light and viewpoint. For richer, more intense results be sure to change not only the color’s Hue, but also its Value.