Necromancy Gameplay - Create Permanent Undead Minions/Servants, plus 2 other suggestions
Now this is a bit more than just one suggestion with what I'll ask, but I think it will add great variety in gameplay for possible future versions of the game, and not just go solo or with other players to progress through the game. First, I think it should be possible for the player to take their Servants with them on PvP raids, NPC battles, and mostly boss battles, besides Servant Hunts.
Now, unto the topic: if anything like the previous suggestion ever happens, I would also suggest some manner of Necromancy for the player to create Undead Servants, and act the same as the Human Servants who have turned into vampires after conversion. In several vampire stories, they can command the undead, animals, etc., so I think it's more than obvious for a good vampire gameplay, and for role-play aspects even. Maybe a new station/structure would be needed, like some dark skull altar for example.
Also, final suggestion: Servant Skins. I'd like to see dark-themed Servants, even if just reskins.