Aye, I'd agree with a). I don't like how they kept on bringing people back - it was alright for a cheeky thrill now and then, but it meant that each character got about three different "closures," which seemed a bit gratuitous. It made the narrative just a wee bit jerkier. And no, I don't mind River either. Nor Captain Jack, at that - because both were clearly earmarked as recurring characters. Martha sort of became one, and I think her return in The Sontaran Stratagem was a lot better done than her return in The Stolen Earth, say. Although the Stolen Earth was like a brilliant sugar rush throughout, so I'm not complaining.
Love the Ood though. They were my favourites right from second I saw the Impossible Planet. Really excited to see a Moffat-penned Ood episode. And they've got green eyes! Eyes of green! Which are eyes! With green! What's going on there?! I like the Ood as they're the first sort of "iconic" recurring villain that the new series have produced. They're RTD's Daleks. The law of diminishing returns operates to a certain extent - Planet of the Ood wasn't as good as the sublime Impossible Planet, the appearance in The Waters of Mars was chilling but ultimately meaningless, and they were just there in The End of Time, but they're a brilliant design and a brilliant concept, and I really relish seeing them. (Also, I like how they're in each even-numbered series. That's a nice touch.)
The thing that's exciting me most, though, is the Silence. Apparently we're introduced to them quite early on in the series, and according to Matt Smith they're scarier than the Weeping Angels. I can't wait.
Do wonder if the Weeping Angels will be back, on that note. I'd possibly hold off on them for a couple of years, though. Maybe have them as the big bad in Matt Smith's last series - form a nice Weeping Angel trilogy. They've had two corkers so far, a third would be grand. Could make it a three-parter, too, so their stories get progressively longer. If they continue to be used this well, they'll definitely be Moffat's Daleks. I think they might be already, even.