So I don't actually have a myriad of well organized thoughts on this episode, but I did have one particular observation that I feel compelled to share.
I thought that the monster love story twist at the end was rather clever, and I liked it. From the few reviews I've read, it seems like the general feeling is that is was a cheap twist. When I was watching the episode and the doctor has his revelation about the monsters real purpose, I actually laughed out loud.
Everybody knows that the second you get a good look at the monster, it stops being quite as scary. No effects team can create something that caters to your own personal fears nearly as well as your own imagination. So I thought that what the story did was quite clever. When the time came for us to finally get a good look at the terrifying creature, we knew that we no longer needed to be afraid of it. So the reveal, instead of taking away from the atmosphere, actually supported the story. Perhaps it's my own lack of exposure that makes this idea seem novel to me, but I certainly got a kick out of it.