But she has to be one before the true story reveals, right?
Cleric? Not at all ...
Worshiper, yes.
But that is entirely different case.

Free your mind of shacles of Class ... your character can be much more than their abilities!

Count with me ...
Why Shadowheart cant be Shar worshiping Paladin?
Why Shadowheart cant be Shar worshiping Shadow Druid?
Why Shadowheart cant be Shar worshiping Rogue?
Why Shadowheart cant be Shar worshiping Shadow Monk?
Why Shadowheart cant be Shar worshiping Sorcerer?
See? It works.
But since this isnt my first rodeo i allready hear you saying:
"But there are other classes, that dont fit so well!"
And you are corect ... it would be quite odd for her to be a Wizard ... since Shar and Mystra are not exactly besties.

But i would like to point out two counterarguments:
1) This is choice you allways make willing and by choice ... there is no way for your Shadowheart to "accidentally" become ... well, whatever you dont like.
And even if you would somehow manage to break her by accident ... you can allways just reset her again and start over. :P
2) We are talking about game where you can be kind and benevolent Life Cleric of Bhaal ... or psychotic murdering Cleric of Tyr ...
So ... what kind of roleplay consistency are you even defending here?

Dude, do you know sth called "sampling survey"?
Sure ...
More than that, i even know what that is! Meaning i know exactly the reasons why it cant be aplied here.

If you want to know them aswell, i listed them several times here on forum.

And if you dont want to search, wich i understand ... the biggest one is written right there in that poll topic.

I believe it was mentioned by mrfuji3, not sure tho.
Also I guess less than "0.00025%" of all players think "it's fine and it should or could be implemented"... I hope you are not serious...
I am ...
But i never said this.
Personaly i see it more like around 99,9995% of players either dont give a shit, or just dont care enough to express themselves.
You know, facts.
And one thing I really don't understand is that you all tell me "if you don't like it, then just dont't use it", and it is not wrong for a game to have more freedom. But adding an option in the game menu is also adding more freedom, and I don't know why you are against it. All I ask is one more option, and if you don't like it, just don't use it. I'm not ruining anyone's game. Actually, it would surprise me if your game experience were ruined by an option.
On the contrary ...
Im arguing for that option!

It doesnt matter to me at all if i need to unlock and confirm it trough several settings ...
As long as i am ABLE anyhow ... to make my Astarion Paladin, im fine.:)