The choice to allow both Connor and Isolde to live? it just doesn't seem like them to have a "luvvy duvvy" happy ending, there's is really no negative consequences.
Yes and no.
I don't think they regret allowing a choice with no negative consequences, and I don't believe choices should always damn players into a decision between bad outcomes.
However, we know Bioware, or at least David Gaider, regrets making that 'no negative consequence' choice too easy to obtain. He admitted he was afraid of fan reactions if players went straight to Redcliffe and were forced into a choice where someone has to die (Isolde or Connor). This is why it's possible in DA:O to get to that decision point in Redcliffe, and then suddenly be allowed to go all the way to the Circle Tower and come back.
He said this after plenty of players commented on it feeling odd, even disappointing, that they could detour to the Tower then come back, only to find possessed!Connor wouldn't have done anything in the mean time.