arn't "zones" (maps) kinda seperated anyway? meaning 1 area 1 map and the zone is show as a open space much like in ffxi? Why not just use the big map and check it to make sure you are not zoning. All the mini map should show is monsters in the area around you. When I travel in mmo I tend to use the big map vs mini map. Since the mini map is so zoomed in.

A message warning people of zoning if on a levequest is a good Idea though. But mini map marker wouldn't work I will just look ugly. (played tons of mmo with them and no one made a decent looking marker)