Hey Luca! Great job on this. Something I might add is it doesn't quite feel like the anatomy is being utilized to design the shapes, right now they make the forms bumpy. What I'd recommend is to try to simplify your drawings a bit with more gesture lines that describe more of what the forms are doing. For example in the draw over I did below, you can explain one of the hands a lot more simply with gesture. From there you would include all of the structure and anatomy stuff. I also included a diagram by @Stan Prokopenko demonstrating what I'm talking about. You want to get the primary form down (the overall wrist / hand) , then from there focus on the secondary shapes (fingers / bones / other anatomy). I'd highly recommend looking into @Steve Huston's videos on gesture. He defines gesture as "the movement between forms". Hope this helps!