The "sort manage events list in front-end" question made me wonder: Out of curiosity, why can only category admins see all events on the front-end managed events? It would seem that, particularly for those not using the JEvents permissions system, anyone with "edit" or "publish" rights, that can herefore modify others' events, should be able to see them from the front-end manager.
As it stands, we can't use the front-end manager because our publishers can't see events other than their own. They have to go into the calendar and "show unpublished" to get access to manage the events.