I'm up for some casual play with a twist during the holidays.

This reminds me of Nimrod's Xmas server which was ambitious but successful enough. https://www.jazz2online.com/jcf/showthread.php?t=11851

I'd say it's okay to use regular old favorites as well as recent event sized levels (such as in Total Annihilation 2) with a mutator that adds christmassy effects to the rabbits, or swaps some palettes. Or something.