See, while I totally get how some people would not like that a bit, the darkness of Fang Rock appeals to me - sure, I wouldn't want every, or even a large amount of DW episodes to be that way, the utter bleakness of Fang Rock make it a great watch, when I'm in the mood for bleak stuff - I can't think of another episode that is so relentlessly oppressing and bleak as Horror of Fang Rock is.
Two quick things that bother me in Fang Rock, though. #1 is really only a minor niggle, but why the hell does the Doctor say that Skinsale died with honour? No he fucking didn't, he tried to clobber up some diamonds on the fucking floor when a goddamn Rutan was advancing on him, knowing fully well that it's gonna electrocute his sorry ass if it manages to touch him.
#2, though, is a real storytelling flaw - not enough to ruin the story for me, but still pretty glaring - the Rutan landed that night, right? So where the hell does the legend of the Beast of Fang Rock come from? Is it all a massive coincidence, or just lazy writing? Now, if I overlooked something, please point it out, but it just seems sloppy, like a cool idea they had at the beginning (it landed ages ago and some people were killed by it, creating the legend), but then just changed the arrival time of the Rutan and not really giving the implications for the legend a second thought. Nitpicking, I know, but eh.
(/SPOILERS).