I believe there should be a new timezone for Trenzalore with Christmas (the town)

In the town there would be Christmas villagers. Not the ones from the advent calendar, but instead they will look like non testificate people

The hostile mobs that would spawn there include: Daleks, Weeping snow angels, The silence and Wooden cybermen

Their would be a small pine forest with weeping snow angels that spawn in big numbers

The cybermen will fire a red beam with flame particles that will set whatever it touches on fire

In the center of Christmas will be a clock tower

The weeping snow angels and the daleks will spawn outside the town but occasionally they will spawn inside.

The wooden cybermen will spawn inside. They will spawn in very small numbers. As in the episode there was only one wooden cyberman

 It's pretty great overall

I added some new text. Is it better this way?

There are a few details I would add though.

Do the mobs spawn in the town or outside of it?

Also, do you mean the Christmas Villagers of the Advent Calender or the ones from the show? (I'm guessing the latter, but it should be specified in the post)