Awesome job so far! Gestures can be really difficult, and its something I struggled with for a long time- what helped me was following Michael Hampton's interpretation of gesture, as a series of relational curves. His videos were like a revelation to me. If you have 40 minutes, I definitely recommend watching this https://www.youtube.com/watch?v=sSzB3ESpfE0 He also has videos of him doing gesture examples. Try to follow along, and definitely pause if you feel like you need some time to catch up. Good luck, and well done so far.

I really like how it looks like a colorful little bonsai tree. I agree with what Patrick noted- if you're comfortable with blender/similar 3D software, it might be worth creating a simplified version of the tree using simple primitives (such as UV Spheres for the tree canopy, and using a simple vertex path with a skin modifier for the limbs) along with placing a single light source to help visualize the value change as it turns away from the light source in the tree's canopy. Overall its a really cool design. I do a lot of work in blender/3D art as well as 2D, so I'm looking forward to seeing how this turns out. Let me know if there's anything I can help with.