You know, in my view, Tav is the least important part of the story. What determines *the* ending is your faction choices, major decisions during/before the ending, etc. That also means... your origin character can end up fucked despite the ending not being bad.
The aberration? The dark urge. It's the cumulation of "what's normally smart doesn't apply to you". It's the path for people who don't want to suffer from destroying relationships and burning bridges. Tav doesn't have these privileges. The gameplay will be more varied for it. It pleases people who want to be the edge lord supreme, but also people who want serious storytelling and consequences.
Do you know how the dead three became gods? Or more specifically do you know what they were before they became gods? The dead three were just an adventuring party the same as our party...the potential resolution is literally right there under your nose...baked right in the very foundation of the story. They wanted to fight Jergal for his powers but Jergal got bored of his duties and offered them his position. But since neither of the three wanted to share power and neither could defeat the others the duties were split among the three. Now the dead three are working together, if we defeat them there is a very good chance our party could choose to replace them...new gods of tyranny, murder, and death...but more importantly they would be gods. That's a very straight forward potential resolution to getting rid of tadpole after taking a ton of powers from it. Another resolution...ally with one of them or Shar. Each of them wants to come out on top after this conflict...you can almost certainly broker an alliance with one of them. Your entire focus on the point that "but act one said it was impossible" is misguided.
