Personally feel you guys are being over-critical of DW, in fact, a lot of fans of the show just seem to be nitpicking at everything. Instead of criticising the writing, why not sit back and just enjoy it for what it is. It isn't the same mess it was during the Amy Pond era.
I think this was actually a really good episode, the Cybermen were actually terrifying for once and for the first time since the reboot I felt as though one Cyberman would be enough to destroy a planet. The Cybus ones from DT era were terrible in comparison because the only scare factor they had was their reputation. The ability for them to just upgrade any weaknesses was good too, however, maybe a bit unsustainable.
The emperor was actually quite a good character too, in my opinion. That being said, that girl was annoying and a bit unrealistic. A ~7 year old randomly finds out that her babysitter is a time traveller then decides to blackmail her into letting her go on a trip rather than being in awe. Just to top it off, when she gets taken to another planet she seems so apathetic and isn't grateful at all.
It was nice how at the end of the episode the camera panned up to show a spaceship remaining near the planet though, means they can avoid coming out of nothing when all of them had been wiped out - like they've often done with the Daleks.