'Monitor' is a very good idea to use for a queue of departures. There are few things more off-putting than pummeling those brain cells trying to figure out how you're going to cope with the BPK+4 MDI that's just been slapped on, as well as how you're going to get those two late slots through the crowd and airborne in time and then hearing 'Tower, Fastair123' when you're not expecting it. Ok, so now you need to reply...you wonder what the matter is....'Fastair123'...........'Tower, Fastair123 is holding at S1N'
I can see that, thank you. Now, where was I?
Please, if you're told to monitor, then monitor.
I would recommend, once you're given marshalling instructions past PLUTO/ETTIV/HORKA etc, is to tell is if you're not ready when reading them back. That gives us a chance to do something with you.