There are lots of ways to make that pattern bigger.
For one, try laying out some extra fabric and see how it looks with sashing between each block with matching or darker/lighter fabrics. And then when it's larger, even slightly till it sits on top of the bed, there is no law at all saying you can't add some smaller pieced Christmas trees to a "drop to the floor" edge of the quilt if that's what you want. Or even make the edging with Christmas Tree decorations, hanging balls with a few tiny Christmas Packages would be pretty. Some of the 3D ones that have been shown on this forum recently have been lovely.
Or, and this might be even easier, is to go online and get some coloring book Christmas trees and make larger appliques. That way you have time to add this and that to them before Christmas. I can see it now, with tiny round shiny blobs of decoration on it with silver and gold threads. 3D Christmas presents under the tree with lovely flying ribbons...come to think on it, that sounds so nice I might want to try it for myself!!