Though generally super excited about this title and trust Larian to do their best, I kinda share your misgivings about the origin characters.
It is a bit like playing with premade characters in TableTop: it can be done, it can even be fun at times but it kills a major part of the game, that is creating your own hero to experience the world the DM is building for you.
On the other hand, using Origin characters present a unique opportunity for the writers to create PCs with a real, living and breathing backstory (something I think is always lacking with custom build heroes). For instance, the reason I could never immerse myself with Pathfinder: Kingmaker, is that I felt my protagonist was a total stranger in the game world: they had no past, no personal connections, no nothing.
With its several Origin PCs, I hope BG3 will be able to really situate the player as a character in the game univers.
I reckon the first Dragon Age game really hit the aurea mediocritas there with their origin stories: it was still customizable but with a unique backstory for every new play-through with real consequences throughout the narrative (though imo they could have developed the system further).
In the end, I am hoping that the many origins story Larian is writing (beyond 10 I believe), I will find someone I can really relate to.
I am also curious about what Swen stated about their custom made characters that they will have connection to the game world (even though I am skeptical, as i said I don't think custom heroes will be able to compete with the Origin heroes' immersion in the narrative). Despite all of this, I will surely try a custom hero play-through (I have already built several builds via my Tabletop softwares and sheets, I know, I am such a f... nerd).
And about Larian writing style, I think the developers are really focusing on upping their narratives to a whole new level with this game, hiring a new squad of writers from the get go.
