I too was concerned that the story/writing would suffer with the change from the fixed-gender plot, but it's a little hard to say without knowing the specifics of the said plot. If I recall rightly, Larian did say that they made the change because they realised it was the right one for the game and that it would actually mean a lot more work and writing. I dunno, we'll see how it turns out though in retrospect we may never know.
I do wonder what the writing will be like in Original Sin. I've found Larian's past games a bit 'camp' in that regard, which while fun (and often brilliant) isn't to my tastes for 'my dream RPG', but then the writing isn't what draws me to their games so my expectations/hopes are different there. Yet Original Sin looks to be something substantially more than their previous offerings so I I am hoping for a bit more depth and seriousness, especially with companions now. It looks that way with the dialogue and 'reputation' system they have going on. I'm fascinated to see what Original Sin will actually be like to play...
Actually come to think of it, I think I'm finding it easier to manage my expectations for Original Sin now because there are so many apparently quality RPGs coming out soon that cater to my tastes, each offering different experiences. So I'm not as starved as I used to be and I'm becoming accustomed to that.
I think this happy state of the RPG market might be part of Larian's reasoning for sinking so much extra resources and effort into this game, if I'm interpreting Swen's recent blog correctly. To release a game that compares well and hopefully stands out in a strong market with the likes of Project Eternity, Torment:Tides of Numenera, Age of Decadence, Wasteland 2, Blackguards etc would create some serious prestige for Larian. Not to mention that it will need to be good to get attention with all these other games around. Of course they could all turn out to be forgettable, yet somehow I doubt that
Exciting times!
