The key points covered in this text include the importance of understanding that chunk balancing, data balancing, and traffic balancing are not always equal in a sharded cluster. The balancer focuses solely on ensuring chunks for a given collection are evenly balanced across all shards, but may not take into account other factors such as traffic or data distribution. This can lead to imbalances where one shard receives significantly more traffic or data than others, even if the chunk count appears balanced. Additionally, the text highlights that waiting too long to shard a large collection can be challenging due to limitations on initial collection size and chunk size, but strategies such as adjusting chunk sizes or manually moving chunks can help mitigate these issues.