What do you think about of a Santa Claus version of Wario with Christmas microgames? Could you imagine and mention christmas microgames ideas for Santa Wario? I think, like an idea, the Christmas WarioWare microgames could become to WarioWare games each Christmas month.
Funny enough, WarioWares from Gold onwards have paid more attention to Christmas lately. Gold and Get It Together! both have Christmas-themed artwork released alongside (but not in) the games, and Move It! has a Christmas themed microgame: Presents of Mine.
The concept of Wario being unwillingly forced to take on the role of Santa (from the more usual Mario) by his employees (the GIT artwork shows Penny, Red, Spitz and Orbulon alongside Santa Wario) is a hilarious idea and probably might be worth exploring in a game; maybe not a full WarioWare, but as a side plot in a stage or even a Paper Wario.