Similarly, I sort of think the Moffat-era representation of Cybermen ran aground around Gaiman's episode where they became all-powerful, invincible against everything, able to 'upgrade' to beat anything. That episode really irritates me because the point of the Cybermen (and what separates them from the Daleks) is that they are the science fiction/space/kid-friendly sanitized (IE no blood) version of zombies - the reason them waging war is deadly is because for every one of you that is killed, they gain a new soldier by upgrading them. They swarm you - they don't need to be invincible... which is why they're still effective in Doomsday even though they can't even scratch the Daleks and we see Mickey and his crew blasting them to pieces like they're nothing. Mind, this year's representation of them was better, and it seems like the invincible angle is being slowly eased back out of existence. (Indeed, a weird thing about this year's episode is that when the newer Cybermen start to appear most of them (though not all) are the RTD-era design and not the new, snazzy upgraded design... again. Weirdly they sort of swapped places - the Cybermen became more like the Daleks and the Daleks became more like Cybermen, and neither is as effective for it.
I do dislike the Cybermen becoming more of a generic army, which is why World Enough and Time worked so effectively for me (and Doctor Falls lost some of that good will). I was surprised by Nightmare in Silver because Gaiman just did not seem to get the Cybermen at all (which makes me wonder if they were foisted on him in rewrites).
This has conventiently reminded me of something that's bugged me about Death in Heaven: the way cyber-pollen works is it converts living tissue but obviously Missy making it work on the dead is a big deal. That I don't have a problem with. Just one question:
Why can't she use it on the living humans as well?