Clay trees, real rocks and fossils, and a clay reptile to be added to a thousand and one unfinished projects and to be animated later with a simple walk cycle 
I like the bottom one best. Could you change the lighting / exposure or do some color correction to make the scene blend a little better with the background? Not trying to be a pain in the butt. I have never done anything like this, and am not sure what it would take to match things up a little better.
Nice job! I especially like the camera left tree. And is the dino’s eye glowing?
Looks awesome man. Nice job on those trees.
I would play around with curves in photo shop and bring the darks out in fore ground , you should try doing a claymation thing with that, I like it
Its’ true, the foreground should be the higher contrast. Maybe add some noise to the background, and turn down the contrast, and up the brightness.
Thanks for your comments, your suggestions are noted and appreciated. I am still in experimental phase and I am still learning. Yes, I plan to animate it and I’ll experiment further with diffuse lighting as Modron suggested in earlier posts. I have a mirror and I painted a flat white light reflector on a board so that might help with better lighting. 