I think that the rose itself is lovely and that the geometry, spacing, proportions, and especially the coloring are very nice. However, some of your other work has more detail in the shadows, particularly your pencil-drawn stuff. I think that the shadows could be deeper, with more attention to where the light is coming from and where (especially deep between petals) it is going. It's good now, but I think a little more shading and it would be excellent.