A version of this flaw already exists in one of the sourcebooks. In clanbook Tzimisce on pg. 43 there is a 3-Point flaw named "Privacy Obsession" with two effects:
- Must make a Willpower Roll (Difficult 6) to enter into a dwelling uninvited.
- When disturbed by an uninvited guest in your own home, you must pass a Self-Control check (Difficulty 7) or frenzy.
If you're not interested in having that second effect, but wanted to make it impossible to enter a home uninvited, rather than simply requiring a Willpower check, it would probably be balanced to have that as a 3-Point flaw as well. You're losing one specific hindrance and making one a bit more strict.
It has been a long time since I played Vampire, but - not only is it possible to do a group creation followed by individual preludes - it's the best way to do it.
You will probably need to have a gap in time between the creation session and the first Prelude. There will likely be some tailoring needed once you know the characters. But that's not a huge problem most of the time.
Character Creation for the Mechanics and the Meta
The Character Creation session should be used as a chance to have players become familiar with the system if they aren't already, and to discuss a few details of their characters to ensure they will work together and not have too much overlap.
You also have players discuss meta elements. Perhaps two players want to play rivals. They can discuss these details during this process, decide why they're going to be rivals.
Work up the full character, but I'd suggest telling players that no choices are final. Give them a chance to make changes once they better understand the mechanics and the setting.
During this part of the process, you needn't discuss more than the bare minimum of setting details. You know, just enough to make sure the characters will all fit within the premise. "You're all newly embraced kindred in the crazy world of high finance in the 1980s. Think American Psycho meets Vampire Diaries." Just enough to ensure the characters will work in your premise, and no more.
Prelude for the Setting and Story
Once you have the characters set, you can run individual preludes. This is the stage where you begin to introduce setting and story elements, and it can be run as free of mechanics as you and your players are comfortable with.
It need not be less interesting just because the characters are mortals. But making a story compelling does depend a lot on the GM. If you make the journey memorable, it will be awesome.
The last time I played Vampire, my GM did it this way. I built my Assamite, and then we roleplayed his journey from boy, to man, to trained assassin, right up to the scene where his mentor bites him on the neck and then hangs him up on a meathook. It was horrifying, and gut churning, but it was never dull. Along the way, my GM hinted at what it meant for the future.
You mentioned Initiations in Dogs in the Vineyard. As a GM, I've used this idea in preludes for other World of Darkness games (and other games) to help make them memorable. Players make characters, and then I ask them to ask a question we will answer during the prelude. This helps keep them engaged as they search for their answers.
This way will preserve nice balance between player agency and GM mystery. Players have freedom to create the characters they envision within the limits of the premise, but the GM doesn't reveal too many secrets too soon. I've played it, and run it, and it works well.
Best Answer
Ghouls that are fed for a long time, as well as those that are frequently overdosed suffer a lesser version of the clan weakness. Here comes what Ghouls: Fatal Addiction tells:
I think this contradicts a little other books where ghouls inherited weaknesses last more than that overdose. But I cannot recall which books. Note that it also tells that only some clans' vitae is contagious. Let's see the given examples:
[*] Note that overdosed ghouls already have increased frenzy rating, so you should adjust a little here.
Why those clans? I guess because they were the ones that they could thought better mild versions of the clan's weaknesses. Anyway, one can easily imagine a mild version of any weakness, and they left room to you for coming up with your own.
Note that there is a V20 Ghouls supplement coming, and I think we will see changes to these mechanics, and even a complete list of clans and weaknesses.
As a side note, I remember a funny conversation when people tried to imagine these weaknesses applying to animal ghouls (a Ventrue dog only wanting to eat some brand of food, a Tremere antitribu bird identified as Tremere antitribu by magic users, a Gangrel cat that gains other animals features, an Assamite panther that can no longer drink Kindred blood [or addicted to it],...).