Prompted by ugavine's inquiry on the DWAITAS board:
One for the players. Do you prefer existing Monsters? Or do you like the GM to come up with something new and original? Or a bit of both?
To which I responded:
I'll ask, but I'll note some tendencies.
Players who aren't big fans tend to prefer new monsters, since it puts them even with fan players. This can be partially allayed by using existing monsters in a new way, which is what most writers try to do anyway.
Fan players are more likely to get a kick out of facing the classics. Fan players whose characters have a lot of knowledge of the universe might like the chance to show off in-character. (Of course they can do that with new monsters as well, as their characters could still know all about them, but this requires more prompting from the GM.)
However, both kinds of players generally like surprises. A new monster, a classic monster used in a new way.
But if there's no Dalek episode in a whole series, fan players might feel shortchanged.
And on that last note, Siskoid collating ... Of The Daleks stories lead to the idea of an ... Of The Daleks story with no Daleks in it.