Call me overly simplistic, but my understanding was that Tav was the option for players who wanted a completely open-ended PC, and Dark Urge was the option for players who wanted a PC who was still a custom character but was tied into the world and had an established questline.
I agree, but I think the problem is that a lot of people don't want the graphic violence of the Dark Urge, yet still want to be an integral part of the story. Also I think that marketing messed up when they promoted Durge as evil, so many folks who don't play evil won't even consider it at all. I know I started maybe ten Tavs, getting frustrated with each character because she was so disconnected from the story that was supposed to be a continuation of the previous Baldur's Gate games. Then I researched the Dark Urge and realized that's what I should have been playing from the start.
In the previous BG games, you have a backstory, an evil one (unbeknownst to you), but you are able to build your character the way you wish, and avoid the horror while also being the main character of the story. Larian failed to to this on so many counts -- the custom character is too generic for most players, and the Dark Urge is too horrific for most players.
