This has been brought up few times already. I suspect this is an issue due to multiple factors. Lack of strong design direction and abandonment of the initial designs were mentioned in the press. Th full loot PvP centric gameplay and Native American theme were dropped, as these were considered as controversial. The game also faced the usual development delays, which often lead to cut content.
I feel PvE experience and general game world depth could be improved if new factions were added to the game.
In the initial trailer we have seen Ancient Romans. I'm sure I also seen mentions of Vikings. The initial game designs included native American inspired factions. I would love to see these added over time to the game. Native Americans could even act as a neutral, non-hostile faction with some NPC run villages and quest lines explaining some ancient lore. Also with all this occult inspirations I think we could really use some more demonic and Lovecraftian creatures in the game, so we face less humanoid mobs.
What else do you think would fit the present game vision?