General Antonyms:
* Lack of skills/abilities: incompetence, ineptitude, unfamiliarity
* Limited range: narrowness, restriction, confinement
* Absence of a collection: scarcity, paucity, deficiency
Contextual Antonyms:
* For an actor: amateur, novice, beginner
* For a musician: improvisation, spontaneity
* For a writer: originality, innovation, freshness
Other Considerations:
* Antonyms can be relative: A large repertoire might be considered an antonym for a small one.
* Antonyms can be situational: If someone is known for their vast repertoire of jokes, their "repertoire" could be considered an antonym for being serious or somber.
It's important to consider the context of the word "repertoire" to determine the most appropriate antonym.