we decided it was not user-friendly to have a createConnectionFactory will all the parameters in the management API. If the user wanted to change a single setting, he'd have to specify explicitly all the defaults (which is a PITA when using a GUI console since all the numbers will default to 0). It is more user-friendly to create the connection factory with the default values and then change one or two attributes directly on the ConnectionFactoryControl
JMSServerManager provides additional createConnectionFactory methods (with all parameters) which can be used when the user directly instantiate the JMS HornetQ Sserver. In that case, he has access to all the defaults constants through the classes and it's more convenient to let him specify the settings directly when creating the connnection factory.