To redeem Lancel a little and give the audience an insight to what was going on. Let us hope that Cersei didn't actually 'plan' for Lancel to suffer like that somehow. That's a bit much.
One pet peeve I have with the North scene. Seriously, Jon casually mentions that the Army of the Dead is coming as winter is here. Either the Lords of the North are just accepting that the WW are real, as are wights and zombies and that's just how it is. Or they're just nodding at Lord Snow (Stark) like he didn't really mean to say it.