My guess and wish would be PVE areas like in the Albion Online Beta (back then before they reworked the world map). You had open dungeon areas, accessed by a gate or something and not instanced at all, just so it is not 100% obvious to the enemy right away (like the gate at the temple in gods reach). At any time during your "dungeon run" you were able to being raided by another group that just came in while you were fighting mobs, pulled more on you and your group and killed you first and the PVE mobs afterwards. This was a "perfect option" in my opinion and i hope we will see similar things like that in CF.
Anyway, I hope some devs read this post and are on my side