I can imagine. The adventurer one is more happy go lucky and treats "freedom" as easily digestible concept without any drawbacks, it's more in line with the wish to make everyone happy. The mood change between romanced Underdark and unromanced Underdark (when he's a companion) is weird to me, in the romanced version he's constantly worried, while in the unromanced one he's more winging it.
In my opinion they made the right call by making this the default ending. I don't think he should be responsible for the other spawn, but only for himself. Well, in the romanced version he has to worry about a juicy meal walking among hungry spawn so I can imagine it taking a toll on him.
