Since you wanted to keep it "as is" (and it is wonderful) I just tried to enhance what I saw as strengths. I darkened up the snow a bit, lightened the shadows and midrange, tinted it a little with some sepia tone taken from the background, used a blend to fade the treetops a bit and got rid of the logo on the umbrella. Oh, and I took too sharpening passes, one a 1 pixel and another at .5 pixel to bring out the snow more.

Kort Kramer - Kramer Kreations