A message such as "EZ 123: cancel take-off clearance" is not clear and does not convey a sens of urgency
That phraseology 'Hold Position, Cancel Take Off' is only used
before the aircraft has commenced its take off roll which is why you probably don't get a sense of urgency from the message but it's repeated twice and very clear.
If the aircraft has commenced its roll then 'Stop Immediately' x2 is used which does give a sense of urgency. What is more important though is the way it is given to the pilot so the urgency really comes from the voice of ATC and not the wording.
I agree with you that further instructions after a Go Around should only be given once the aircraft is in positive climb unless there are overriding safety implications.