I think the one with the darker wood for the Iris and stems is the newest, most recent one. The one with the lighter overall woods is the first one you did. I say this based on two things. Your choice and variance of more "wood" color in and the more aggressive shaping that appears to be have done in the one with the darker wood. From my classes with JGR and other information I have learned from books, articles, blogs, my own limited intarsia work, and observation of others that is the two areas that tend to show the difference in beginning work and those more experienced. Beginner first use the wood they have on hand which tends to give us less "depth" of color to the piece. As you progress, you start expanding and widening your wood "collection" so that you can add the depth and color to give it the "art" look of an advanced practitioner's work. Then beginners tend to not want to take off too much wood when shaping/sanding. We don't want to "mess it up" so we leave it more flat. People who advance their skills learn to be more aggressive in their shaping/sanding. Realizing the more you shape and sand the piece, the more depth and dimension it is going to have and the more realistic it is going to look.
Thanks for sharing your work. I like seeing others to learn from as I try to progress with my work. Both are nice, but you can see that your skills and confidence in shaping has grown in the two years you have been doing the work.