Best jungle for Bronze 3?

I'm having a problem because Zac and Maokai doesn't seem to deal enough damage to carry a bronze team. I have a lot more success with Vi because she is capable of getting kills on her ganks. The problem with zac and maokai is they need a good team to take advantage of ganks and well that just doesn't happen very often in bronze. What is the best jungle champ for carrying a team at the bronze level besides master yi?