No, Sven didn’t recommend Durge for first playthrough because he things Durge’s content will have more impact, if players knows the default chain of events.
It seems we won’t always be able to stop our murderous urges - sometimes thing will happen and we will be left to deal with consequences.
I think the main feature of Dark Urge is its additional, extra violent dialogue options.
Even assuming you don't start killing your own companions to get more power, it can lead to minor or major changes in some events.
It is reasonable to assume that a large number of people who are determined to play as a psychopathic killer will play as a psychopathic killer.
This will open up some new content for you, but it usually closes it off a lot more (for example if you kill a companion).
Therefore, it is recommended that you first know the default (and in this case probably richer) chain of events.
It seems we won’t always be able to stop our murderous urges - sometimes thing will happen and we will be left to deal with consequences.
It's one possible explanation, but for now you have no more evidence for this assumption than I have for mine.
