What a cute little fellow! You might consider opening up the shadows a little (Shadows/Highlights in PS) and perhaps some cropping from the left and bottom. The twig poking his ear and the twig shadow across the little fellow's head are unfortunate, but whether to retouch harks back to the intent/artistic license issue raise in another recent thread.
I agree with Karen.
You might selectively open the shadow on the head and shadowed body rather than a global adjustment, or open the shadows locally more than the global correction.
The reds look oversaturated to me.
I'd also crop a bit from the right to eliminate the vertical branches. Then see if you need to crop a tad from the left to rebalance the image.
Biggest problem with these images is getting a relatively clean shot with less shadows and, even better, fewer twigs. But nature doesnt always oblige.
Enjoy the new lens!
Scott
