Very cool Rick!
I think my favorite is #2, but I don't like the red rope in it. I see what you were going for, but I don't think it works.
Now my 2nd favorite is #3, and in that one the Selective Coloring does work. Maybe because it's blue and a bit darker and just blends in? But I like #3 a lot.
#1 and 4 are also nice, you are doing a good job on your technique.