Any chance that the system will be modified - perhaps via a plug-in - to enable "open" events - those where anyone can register without having to be a member and are notified by email of their registration with a link to cancel should they wish to? - could be a form filler front end that can be configured by the system admin to define which fields on the form, including which ones are required. Members could also enroll, or be assigned to the event - in roles - such as event leader, etc.
Thanks
Bryan