When creating connection pools using mongoc_client_pool_new() the default values for _mongoc_client_pool_t.min_pool_size is inconvenient.

By default, its value is zero and it appears the only way to configure its value is by passing it on the uri.

I think it will be way more convenient to let the developer of a specific component using mongodb to decide the pool and other pool object settings programatically rather than rely on they being passed on the uri.