What would Christmas be like on DS9? Worf would celebrate it Klingon Style, as he did as a boy in Minsk or wherever he grew up. There would be much freshly slain Roast Beast to share after the Feats of Strength and Klingon carols.
Jadzia would love it and have tales from different lifetimes getting in different Holiday adventures on Christmas, New Years, Chanukah, Kwanzaa, the Winter Solstice, WWIII Winter Armistice Day, Andorian Tuesday, etc...
O'Brien would burn the turkey and Keiko would suggest they go out for the new Klingon place on the Promenade.
Odo would overhear Kira say how much she liked garland from her last Christmas with the Siskos back on Earth and would order some from Quark, who'd try illegal stuff and find himself in custody, forcing Odo to secretly pretend to be garland, while Kira searches to find him for them enjoy the magic of it all together.
Julian replicates some mistletoe for Ezri who misunderstands and tries to eat it. While she recovers in the Infirmary, Garak gets it to work properly.
Martok shares Worf's hunting Santa program and falls to his Game Death from Santa’s sleigh traveling at 60,000 kph somewhere over the Pacific, half of Santa's ear in mouth, and multiple Elf candy cane darts deep in his flesh.
Brunt and Quark declare a truce and partnership to capitalize on the season. Business is great, especially for gullible aliens buying anything that is Christmas related. “The Orbs of Jesus,” known as Jack-o'-lanterns on Earth, made a big splash with Pah-Wrath cultists especially. And Morn.