Since you are doing a "rocky" terrain right there, northrend rock tile mixed with snow, and dirt would probably look fine.
About the trees, remember that there don't have to be snow on all trees, a lot of the trees usually look quite dead during the winter, and there is a bunch of nice "dead" trees in the UTM.
And I just told you that I couldn't see a big dead of playability in that screenshot, but sure, I don't really care.