I think these are good points you raise, Pip, and I know that you and I have talked at length about what can be done, and you have put yourself forward in a role of a somewhat mediator, which is appreciated. But, that raises another question, what if, as in this case, the King does not wish to speak to the rebels or is absent for large amounts of time?
Trying to speak objectively here, I believe the burden of action must fall to the Rebels, as they are the ones dissatisfied with the King/Queen and frankly, it comes down to either fish or cut bait. A stalemate doesn't do anyone any good, especially if one side, or both, are not willing to at least have a courteous discussion about things. The whole point of a rebellion should be to get things accomplished, not just raise a stir, then sit around fighting and bickering. I think the fact that the Rebel system was put in place is tool enough for those who wish to make real, [b]positive[/b] change.
I don't believe that Rebels can [b]only[/b] get things done with the help of Mur, and in the end, I believe that there was too much pressure placed on him to step in, and I own up to my part in that pressure. However, if a rebellion feels that there are repeated offenses, or that their voice is being ignored or silenced by the King, there are ways to make it heard; the Council, gathering support of other people and the use of a mediator, among other things.
One of your question was, "does a rebellion get anything done?". I think it is too early to tell, but I do believe that there needs to be a way for citizens who are unhappy with their Ruler to speak out, and to make changes if there are enough people to support the change. The Rebel system may not be perfect, but I do not believe enough time has passed to say that it has failed or that it needs to be altered.