the colors for both are really nice. my eyes went to the pink one first because it had the brighter color of the two, and then when i look at it more, the red gives more contrast to the branches and the smoke (?). i think doing a gradation of the two colors will add some variety to the sky.
There is some beautiful stuff going on here. The quality of your linework is really getting lovelier and lovlier.A few very quick things that I noticed: The boot tangents at the bottom.The backpack doesn't look as lovingly drawn as your figures. Need better reference maybe? I wonder what it would look like if you were to take that bg tree and extend up another mass of it to sillhoette the middle guys head. I know you are trying to make him stand out- but something about where that tree stops is bothering me...Mostly I really like this piece though! your characters are fantastic!