I agree that parts of the series are getting better, the story in particular. And seeing a death happen first-hand was pretty cool too. But everything else got worse I think. I'll concede the grieving point, you're right. But the stupidity of the characters... I won't back down on that

It's not difficult to stay alive in a situation like this... simply STAY TOGETHER! Unless the killer is Natsuhi (since she has a gun and could potentially kill them all without getting killed herself), the murderer can't act. There's no way a "normal" person (taking Beatrice out of the equation for the time being) could kill one of them without the others knowing... thus keeping them all alive. It's common sense, which apparently none of the characters have

If Beatrice is the killer, then they're all screwed regardless of what they do (again though, it still goes against common sense to split everyone up). The only one with enough knowledge of magic, the spell thingers on the doors and the like is Maria... and she's already sided with Beatrice apparently.