Just to chime in, I think the new series, both under RTD and Moffat has been very respectful of the classic series. Yes RTD steered clear of a lot in the early days, but that was clearly intentional to reintroduce the character with as little baggage as possible, and once he'd done this he gradually introduced more and more of the show's history into the modern incarnation.
Don't get me wrong, nothing would give me greater pleasure than to see Peter Davison pootling around the universe with Ten and Eleven, but just because that isn't going to happen it doesn't mean the anniversary special is going out of it's way to disrespect the classic series, and at the risk of flogging a dead horse I'll cite Star Trek again. Trials and Tribbleations had no new footage of original series cast members in it, Flashback did, yet I know which was the more enjoyable, and the more reverential.
I don't disagree with anything you wrote. And totally agree that both RTD and Moffat have been very respectful towards the original series.
The only thing I'd add is to your Star Trek analogy. As it worked out, yes, Trials and Tribbleations was better. However, it needn't have been that way. It all comes down to execution. If Flashback had been executed better, we might be holding that up today as evidence that the classic actors must appear.
In the end, I just want a good story that is well executed. My preference is that such a story includes the original actors. However, if it doesn't and it's still a good story, I won't be complaining!