I thought they did a really good job with the episode. To me the series is a lot like Quentin Tarrentino's work, well done while always keeping the violence so removed from reality that it's never really scary to me. Things like "The ring" or "The Grudge" do bother me but Dexter just doesn't.
I think having him have a child is an interesting twist because, after all, in real life people don't need to be good or decent to be parents, all they need is working parts. It's an ugly reality but it is reality and the show is all about looking at uncomfortable truths.
Entertainment is a distraction but art makes you think.... Dexter always leaves me thinking.