I thoroughly enjoyed the Doctor taking himself out of the decision on whether or not to blow the moon up. I think the Doctor should do this more often. It's not the Doctor's place to decide how humanity lives. He should let us mess up sometimes if we chose to. I totally agree what the Doctor did and for Clara to be so upset at him at the end I think was wrong on her character's part. The other part I really enjoyed was the science fiction part. The whole concept that the moon is an egg is actually pretty cool. We know it's not true, but I wasn't expecting that and never had that idea in my head before this episode. The antibodies looking like spiders was pretty terrifying if you ask me. I hate Spiders and I really hate Moon Spiders. 
Now for the other side, why does Mexico have the only mining facility on the moon? This takes place in 2049, which is not that far off and Mexico has landed on the moon. Did the writers of Dr Who just randomly chose a country at will for this episode? Then just to let you know it's a Mexican mining colony, they throw in a sombrero. I'm sure the when the Mexican astronaut was packing for his voyage, sombrero was close to the top of the list, because everyone knows how useful a sombrero is in space. I'm surprised there wasn't a pinata. Maybe they already broke the pinata and that's where the spiders came from.
The other thing that took away from this episode was Courtney Woods. She has to be one of the most annoying characters in Dr Who ever. I was rooting for the spider to take her down, but it was not meant to be. I don't even understand why the Doctor would even take her in the Tardis. He already has one annoying character riding with him in Clara. He must be a glutton for punishment.
Overall, I give "Kill the Moon" a 3 out of 5 Tardis's. Solid episode.