I have some ideas:

1. Title ideas :** (only if the person is vampire and not hidden)** ----apply to NPC's aswell
Emperor = Grandmaster of the Vampire (name) Of Bulgaria / Dark Emperor of the Vampire (name) of Bulgaria
King = King of the Vampire (name) of Bulgaria
Prince = Prince of the Vampire (name) of Bulgaria
Duke = Dark Prince (name) of Bulgaria
Count = Count (the real life Vlad was a count and most associate the count rank with it so keep it the same)
Baron = Master (name) of (name of barony)
Mayor = Dark Lord (name) of (city)

If you are an idipendent state as a count or duke and its not a kingdom have your indipendent state take on your name (like the muslim) titled for example: Dark Prince Vlad of the Dracul Clan / Count John of the Travolta Clan. (that way you can see other NPC vampire states popping up)

2. Allow for some type of acknowledgement on the character sheet that a person is a vampire. red eyes... pale skin... or a trait of what type of vampire they are. (IF you are not a vampire then you cant detect hidden vampires.... likewise if you are a vampire then all vampires become known to you)

3. a way to track the vampire you create like some kind of psyicic connection!

4. Holy Orders specific to vampire hunting

5. Unholy Orders specific to the Vampires

6. Create a law to restrict or allow other vampires in your kingdom to create more vampires. In addition, create a vampire tree similar to the dynasty tree!

1: Perhaps add a vampire trait that boosts human opinion by a bunch (Basically lets you sacrifice every other member of your dynasty to give you 2 extra points of health, and makes mortals see you as a messiah (Plus 50 opinion), but has a minus 55 opinion debuff with zealots and cynicals.

2: Add an event to usurp the vampire religion if you controll every vampire title.

3: Perhaps some traits for intermarrying with other vampire types? (EG: a Tarsas and a Haineux married, the player triggered an event to have a child between the two, the child would have a "Slightly mixed" trait, apon continuing to mix between these two types the grandchild would gain the "mixed" trait, apon adding another vampire type into the mix you would end up with a "Thoroughly mixed" trait, a very powerful trait allowing for either A: The formation of a new vampire type (Not like the twilight vampires please), or B: A very powerful vampire family tree, with powerful blood traits. (But they would slowly fade out if the line was not kept mixed, simaler to a strong claim turning into a weak claim, before vanishing.)

mmmmm, how about having different paths/ideologies to the religeon, like in muslims and the indian religeons, (the ones that give you extra tech, but less piety, ect.) perhaps somthing like the already existing "house" traits (terfennels, ect.) in fact, you could make the type of vamp you are a decision, ("adopt terfennels ideology" "join terfennals clan") possibly allowing you to change they type you are, but with a cost (general opinion, temporary lowered stats, ect.)

also, i feel that the "invasion" cb needs a nerf, currently, it allows you to take an entire kingdom with no limit to it's use (that i can see). honestly, i feel like ence you gain some territory, you can just constantly ball out of controll with no limiter, perhaps it could act like a holy war or prepared invasion, allowing other members of the targeted religeon to join war, or perhaps a limiter similar to pagan subjugation. (once every decade or so)

phew, sorry for the wall of text, but this mod seems like one of the most promising i've seen, just my two cents.

oh yeah, another idea: perhaps instead of the adoption of a successor, you could add a decision to have a kid with your wife through some kind of magic ritual ♥♥♥♥.

An idea for Prince title coulde be "Bloodroyal", to indicate that the child carries the royal bloodline. Example: Bloodroyal Vladimir of Bulgaria. A norse vampire clan could be "Draugr" vampires. Disregard the draugr in skyrim, read the wiki article on the topic. http://en.wikipedia.org/wiki/Draugr

y'know, there are a lot of awesome ideas in this thread, but i think one relitively simple change would be to add more titular vampire kingdoms, or even just more flavour to the current ones

Perhaps a vampiric cuture that gives bonuses to vampiric rulers?

Two more ideas: Icelandic assault. (For one year per character the player can launch an attack simaler to a crusade aganst iceland, it will engadge a holy-war where the player and any vampires that join them attempt to invade iceland, if they win the whole of iceland will become outed vampires, and the leader of the assault will claim the dutchy.)

Idea 2: Add a vampire antipapacy (At least until you can get elections going, allowing the player to depose the current dracul, and placing your antipope in charge.) Another possibility would be to make a pagan version of the religion (old-gods-DLC) and allow the player to reform the religion and become the Dracul (Germanic reformation).

I like the idea about vampiric anti-dracul, however would'nt the dracul need to be landed, also if he is landed he can also very easily loose his land (christans/pagans/muslims) attacking him with dejure/county conquest/holy war on day 1. Still it would be very cool to have papacy style dracul, with a college of high blood priests, or somthing.

Hmm, make the kingdom of Bavaria vampire territory so that they stand a better chance? (Dutchy of transylvania is in Bavaria for a while.)

*Bulgaria

Idea: Outed vampires get access to a special building called "The crypt", it would give some money every month, and boost the light infantry count by a lot, it would come in three levels, ultimately taking 10000 gold to complete the three levels of construction (Giving immortality more purpose), another idea for giving immortality more purpose would be to add an event (Simaler to adventureres in the old gods DLC, and the family feuds in the republics DLC) where a rival NPC-only clan of vampires spawn and attempt to exterminate you and all other clans, they would be fairly powerful at their starting points, and would spawn in seperate counties forcing the player to spend decades, or even centuries attempting to eradicate them.

A family trait of some sort, where your non vampire family doesn't hate you.

Contra-vampire species? Lycanthropy, could have events where your ruler if they are an early lycan turning against their will under a full moon and running rampant in whichever kingdom they are in and it would be fun to have an underlying fight between vampires and the less or more numerous lycans :)

I am staying away from other mythological species. This is a vampire only thing. I'll leave all of that to Mythos or any of the other ones out there. The mod is not meant to be one where the vampires take the main stage, they're supposed to be hidden and affecting things from behind. I know that's not entirely how the game is modded out right now, but its the direction the changes are going.