-Cheap as hell ending. While Shadowheart and others have to choose between hard choices, Dark Urge just gets rid of their urges, no strings attached. The choice should be between retaining the Urge, their powers but being tormented by Bhaal for the rest of life or getting rid of them, but at a steep cost like living on borrowed time. Or something similar.
This really bothered me as well. I don't feel like Tav deserves a 'perfect' ending here, when nobody except for Gale gets one, and even he doesn't get exactly what he wants, which caused him to be in that situation in the first place.
You can ask Withers to have him let you remember your victims, as a sort of self inflicted atonement, but perhaps having Withers simply force that upon you as atonement would be a better outcome. At least it'd be something.