To help reduce the long connect times you can 'withSchemaMetadata(false)' (http://docs.datastax.com/en/developer/php-driver/latest/api/Cassandra/Cluster/class.Builder/#method-withSchemaMetadata). This has its cons though as "If disabled this allows the driver to skip over retrieving and updating schema metadata, but it also disables the usage of token-aware routing and $session->schema() will always return an empty object."
~Fero