The obvious use for such a feature would be to dump everyone's unimportant stats to 8 to make more efficient combat builds. But dumping Int/Wis/Cha wouldn't affect their dialogue or personality the writers had in mind when creating them. Attribute scores would be disassociated from actual attributes and characteristics, a.k.a "bye bye, RPG". I'd rather experience the characters as the writers and designers intended. I just hope Larian can pay enough attention to make them decent at what they're going to be doing while having the stat blocks accurately reflect their character.

Optimized characters are also absolutely not needed in this game. Combat is more about cheese tactics and pushing people and too easy as it is.

As for Shadowheart, I like her as a Dex based character more. It fits a Trickery Cleric. She's good at Stealth and Sleight of Hand which means she can double as a Rogue, very useful. Using a Crossbow at range or dual Daggers she can conceal to appear non-threatening make more sense for her.