So essencially Origins from Dragon Age, rather then pre-made characters from D:OS2.
On a side note, in D:OS2 you could change character class and their looks to some extend (not the race though). I don't know if the same will be true with BG3. Especially in some cases background seems to be tied the the character. Perhaps at least some range of flexibility (like companions in Deadfire having couple options available) would help. In addition, with multiclassing we still have a pretty wide control over our character even if they start with certain class on lvl1. The weak point of D:OS2 was a lot of freedom but little reactivity or response from the game. Therefore pre-made characters had a bit more meat to them as they had at least some scripted responses.
Yeah, I wondered about this elsewhere.
So you could play Shadowheart as a rouge mechanically, even if everyone treats her as a cleric. It’s bound to break some immershunz, but some people wanting more flexibility could be happy with that. Best to have a big warning saying how much it could break the story.
Maybe worth Larian considering, but if not, it’ll probably be one of the first mods anyway.