These are looking great! Try using more closed shapes. Think about them in a 3D space and how they might fit together. Keep the connection points light and they will start to disappear when you darken the important lines.

The hand is plenty readable, and I wouldn't worry about its proper anatomy yet. Instead, I think you should focus on loosening your lines and making them flow a bit better. They read a bit rigid and nervous as if the hand that drew them doesn't trust itself much yet. Disclaimer: Just another student's opinion, not a master or a teacher in the slightest

You can still do the snail :) Great job with this, you used a good variety of lines here.