Hey Thijs,
Well.....I like the concept but there are few things that bother me a bit. To me this image is about simplicity.....so the partial trunk on the LL should have been eliminated or wholly included......while the light on the leaf makes it stand out.....which it should.....the trunks are a bit dark. Placing the leaf away from the knot behind it.....would also hep IMO. I don't feel you can do anything about it in PP'ing....but just some food for thought as I think you have an excellent concept!