What a beautiful drawing. I love the detail and the concept. Plus, I love drawing portraits because people are just such a blast to draw, so this would be the perfect piece of artwork for me to try and replicate.
Keep the branches exactly as they are, ut, instead of the butterfly wing, make that side a cluster of monarchs flying with some landed on the branch stretched out. Also, shading it so that it pops out and making it more realistic looking.