A commonplace metaphor is not necessarily ineffective, and an unusual metaphor is not automatically excellent. This classification concerns the familiarity or novelty of the connection and treatment; rhetorical quality also depends on context, aptness, intelligibility, and effect.
The conventional lion image may be perfectly suited to its purpose, whereas a highly elaborate novelty may fail to communicate. Thus familiar/distinctive should not be equated with accepted/rejected.
A sound analysis first identifies source, target, and relation; then explains the cause of rarity; and only afterward assesses fitness for the context.