Hey man! It's been a while, finally found my password hahah 
Love the concept you have going on, I don't know how much time you have for extensive changes, but it'd be shame to leave out the girl and creature. They can help sell the idea so much better.
As usual I love the color pallet and you are getting better with values and contrast, but some tweaking still needs to be done.
But first I would suggest that you maybe rethink the composition. When I first saw this, in smaller thumbnail form, my eye was drawn immediately to the brightest spot — which is practically empty because of the atmosphere, but girl is strongest in terms of value and most detailed, and yet she's "hanging on the edge" of composition like that. I added room to the right here and moved her leg more in front and put it to stand on another branch, you know, more on inside, so that her leg is not leading our eye out of the image
Now back to the colors~ Like I mentioned above, you are on good track, but it's still not there yet. I realize this is still wip, but it's easy to lose good base to details. I see you may be working towards this but more contrast and slightly lower value on some parts can really help bring her out.
I didn't go too hard on it, but here's some main points:
see below next img
Part of the branch she's standing on is darker, gradually becoming lighter. Yours is just overall too light, but we're supposed to get impression that it's going away from is, in which case gradual is a way to go. Also did same with branch above her head and I "separated" it from those leaves in top left corner
Buffed up foliage in foreground and added more vines around the tree and branches. More isn't always better, but with organic stuff leaving out small details like this and leaving it undefined can make it look "fake"
Made her skin more saturated or "tan" if you will. There can be more saturated points on her, like yellow part of her outfit, but you want to be careful with those accents as well
Added those bright spots on add(glow) layer for that effect of light passing through treetops or whatever... that could look cool since she is under the tree
And I agree with anatomy stuff @rgdraw mentioned. Leg can pass imo but boobs definitelly need correction xD here's img with those notes as well
I would make the creature in the back more visible as well. Applying atmospheric perspective is a good practice to have for showing depth, but if he's relevant at all, wee need to see slearly what he is, because he is set up to be secondary focus in the image from what I can tell.
Hope any of this helps and you manage to apply some of it before deadline (or after) Good Luck 
