I've realised I made a significant typo in the Casanova thread. The "Ummm..." reference was supposed to be for 12.19 rather than 15.19. It's just amazing coincidence that something equally appropriate turned up. Check it out - the actual thing is even weirder.
I thought so. With Doug, it's harder to narrow down specific roles, but I'd suggest examples from Atlantis II, Hopkins FBI, Jack the Ripper, and Dracula 3 as a starting point. Having said that, I would go for John Yesterday from the eponymous series (as well as others), Sork from Of Orcs and Men, The Narrator from Alfred Hitchcock presents (just for a laugh), The Magician from the first Rayman game, the camel from Twinsen's Odyssey, and, if you can get it, Betameche from Arthur and the Great Adventure (I keep forgetting about that movie - and that David and Paul are in it as well).
With Ed, you have a much narrower field to play with, but I'd hope you'd include another clip of Thanatos.
I haven't really thought about Doug that much, but I have some suggestions for Paul. Specific roles would be Richard Julian and Herb Forsyth from Chris Colorado, Kha-Beleth from the Might and Magic franchise (choice between his Heroes V, Dark Messiah, and Shades of Darkness takes), Mr. Silkner from Jack the Ripper (notably when he calls said killer "The Michelangelo of Murder"), and I suspect you'd want to do Dracula (but would it be his Beast or Regal take?). I'd also suggest stuff from Arthur's Knights, Lost Eden, and the Atlantis series - your choice there.
Sorry if that went off topic. I'll come back with roles for Doug later once I've had a think.
As an update, I heard back from Bela Grushka, and she confirmed that she was in On a Paper Crane, and that she played the mother. That's not a character I recall, but if that's the case, she doesn't seem to have been one of the main four (the second tourist isn't really a mother). That certainly rules her out for Sadako, at any rate.
Also, remember how, a while back, you did a montage of David's non-DBZ roles? Have you thought of doing something similar for Doug, Paul, or Ed? If you don't want to, that's OK, but I just thought it was a cool idea.