Personally I'm interested in Christmas themed skins like the current ones for noble residences, but I'd like to have a little more variety to make a real christmas village with workers walking around and whatnot. Gingerbread houses made a good theme residence, but we need theme workers. While my idea came in relation to the christmas event, perhaps it could start with some easter or halloween themed production building skins.

Some specific theme building skins i think could be very cool to play with:

Spooky Farm
Pumpkin Wheatfield
Haunted Mine (a skin that can be put on Industrial or Endless mines)
Haunted Sawmill

Winter School
Eggnoggery (Friary and/or brewer skins)
Holiday Butchers and Bakers (and candlestick makers!)
Festive Homestead

Honestly I'm sort of drawing a blank on Easter suggestions, but you get the idea.