In which The Green Ood causes excessive thought...
Putting a hint of a Dalek into the trailer at the end of my Shalkaverse short story, I made the light from the eyestalk blue without really thinking about it. A 2005-2010 Dalek eye. But the Shalkaverse is a parallel world where the show came back via the web in 2002, so nothing from the Davies and Moffat eras is necessarily true, not even the Paul Cornell episodes. So why should Daleks have blue lights? Shalkaverse Daleks could be completely different.
If a monster reappears there's no reason it can't be very different from previous appearances. Even if it was one way a few episodes ago, the next episode could be set centuries apart for the monster.
Of course, the show doesn't generally bring back old versions of monsters who have been revamped - I doubt we'll see the cloth-masked Cybermen again, because they dropped them as soon as they had a bit more money for the effects. Big Finish and the comics (and probably the novels) have featured them, though.
But anyway, you still have free rein to do something leftfield with classic elements, and if it doesn't work (and the players don't like it, or Doctor Who Magazine's lettercol fills with complaints) you can go back to basics next time.
Give some thought to the changes, the reasons behind them as well as the effects of them. This can be as simple as "we have more money" or "I found a really neat Dalek redesign on the web" or as complicated as "this is a story about the end of the Cybermen where they transcend metal and free themselves, making the universe a better place from then on with their millennia of stored knowledge, so the last metallic Cybermen have to be pretty strange" but it deserves thinking about whatever the case.
And revealing a bit of the new look is likely to cause some speculation about it.
... Why is that Ood green?