Goal order
At the moment one could use a non-integer as goal order. For the applications rtc-tools is targeted to I don't see any good reason why a non-integer order would make sense.
Should we impose order to be an integer? If one wants a something different he/she can always use order one and create whatever function needed.
I don't have a strong opinion about this, but I wouldn't mind to introduce a check to prevent typos/unconscious errors.