Thinking in sepia tones

Now that the background is established, I thought working on the sepia tones first would be best. The tricky part is figuring out what is "in the past" and what becomes full color. The cowboy's hat and head along with the horse's tail were easy calls.

One thing which makes this a very different piece for me is that there is basically no hue. I am trying to think of a warm-looking black and white TV.