Yes, I suspect even taking the path of resisting the Dark Urges will get pretty dark. Though I guess there's an argument that desperately fighting against an unknown darkness inside ourselves in some ways requires more goodness. Certainly goodness would be harder earned!
I definitely got the impression that resisting the urges was a totally valid path, but I'm not sure whether you then end up missing a lot of what makes the origin compelling.
Personally, I'm going for a custom Tav in my first run, and expect to be broadly satisfied with how they are connected to the world and the reactivity to their race and class, with any gaps supplemented by my imagination. For me, the flexibility to play a character I create from scratch myself is more important than having the game tell me a story specifically about them, but totally understandably preferences do vary.
The good news is that we can have it all. If we're tempted by the Urge but are worried it will get too dark, we can always give it a go, and then if it's too much restart with a custom character. I imagine that it'll become reasonably clear fairly quickly what we're letting ourselves in for!