In macro shots the most important thing (as with almost any subject that is alive) is the eyes. This frame, while colorful and having good DOF, neglects to portray the soul of the beast, largely because more of the frogs posterior is featured than his face. The second hallmark of great macros is radical subject isolation... in other words, you should attempt to place this frog against a monochromatic background (either all green or all black/brown, rather than the mottled green/black background evidenced here, the top 1/3rd of the frame is distracting to me at least), by maneuvoring your position around the subject. I realize this is a little hard with the 80-400 lens you are using, which yields an effective f/5.6 at the focal length you most likely captured this frame at, but keep trying, because you have excellent working distance with that lens, and it appears very sharp from the section of the frame that is in focus. Thanks for sharing a wonderful frog from a very cool island.
Great vibrant colour and nicely composed. Focus on the leg is a little soft, but the eye and belly show good detail. I guess a little more light would have given you a larger dof and I could have enjoyed green tree frog toe detail. I love tree frogs toes!