it sounds like the RMN thing is much more than a project, rather an "Area of Responsibility" (i.e., it's nothing to be finished in the foreseeable future, but an ongoing thing in your life). Thus, I would create a folder for RMN and then put related projects in this folder. This can be a subfolder of "Music" to reflect the hierarchy. You could now also create a subfolder in RMN for each larger project (the festival) to group projects related to this particular festival.
For each of the festival facets you can create single projects ("Marketing", "Publicity", "Prepare for Act X", "Prepare for Act Y", "Prepare for Act Z"). For each workshop you can create also a project "Prepare Workshop X", or a single project "Organize Workshops". The inviting list can be realized as an action group in e.g. the Publicity project:
- [Project] Publicity
-- [Parallel Action Group] Send invitations
--- [Action] Alice
--- [Action] Bob
--- [Action] John
Regarding the people and bands: Actions involving the local government could be either "Discuss parking management with local police @ Errands" or you create a context for the local authority if you expect to work with them a lot. Creating new contexts for every little thing messes up your contexts list - however, you can organize it hierarchically to clean things up again and you can drop (or delete) contexts when not needed anymore. So, to be specific, your contexts list might look like this:
- Band A
- Band B
- Festival Town
-- Tech Crew
-- Local Band C
You can also assign actions to "RMN" if you have things to address in group meeting, for example.
However, having said all this, it could well be that a flat project folder hierarchy and a flat contexts list suits you much better. Personally, for people I only have a "People" and a "Boss" context and specify details in the action text, i.e. "Ask Bob to help me with XY @ People". And two weeks ago I cleaned up my folder hierarchy to only contain "Goals", "Personal", "Work" and "Science" (I am a scientist - "Work" contains projects which are not scientific per se but rather administrative or supportive for my "Science" projects).
I realized that I cannot keep progress in N areas of my life simultaneously, so I narrowed the list down and only keep a bunch of projects active at the same time. In my weekly review I put projects on hold or activate them depending on which I want to work on next week. Showing active projects only during weekdays then shows a simple and non-overwhelming list of projects that are important this week.
Oh, and you might want to break down larger projects as well - for example instead of having a "Marketing" project with "CD" and "DVD" action groups you might as well create two projects "Festival X Marketing: CD" and "Festival X Marketing: DVD". This way you can put them on hold independently to narrow down the amount of currently active things and (most importantly) you get more rewarding "Project Completed" clicks in the same time. ;-)
Ok, enough text for now... hope this helps,