Thanks to all for the feedback.
I am slightly surprised by the unanimous choice of #1. My personal preference is for #3. Don't get me wrong, I love #1, too, but I shot it because, to me, the scene was slightly reminiscent of a very popular Ansel Adams photograph done in Yosemite, "Trees and Snow" (attached).
So #1 is a bit of a copy-cat image, whereas with #2 and #3 I tried a more original take, cropping tightly down to basic shapes. As well, in #3 I left it as a full colour image as I particularly like the subtle colour of the sky. I also like the contrast of the repeated triangles of the conifer against the quite vertical aspens and birches in the background.
Anyway - thanks again. I'm enjoying this forum for the insightful and frank discussion.