As you say, all the characters had superb scripts. Even Rhys played a much fuller part. Gwen's character had moved back to being the central role, as in the first series - and she had some fantastic lines.

I think it's still open enough for a revival in a couple of years. Once Gwen's had her baby, Lois will almost certainly feature, and obviously Martha's still available. Andy the policeman knows too much about Torchwood to be left out completely too. Given that Jack's pretty much guaranteed to pop up in the next series of Dr. Who, he can keep the link alive.