I think you're focusing too much on filling the body with a solid color. You will probably benefit from using a single line stroke for the body, just as you have done for the head. Be mindful of your curves as well. It looks like you're losing symmetry in some places.
The thickness of your strokes is right on the bottom samples, but I would lose the beard. It looks more like a bearded snake than it does a lion and snake combined. Consider using a lion's head, but replacing the tongue with a snake tongue. Or perhaps replacing a lion's tongue with a snake entirely. Just my opinion, but I don't think creating an animal hybrid works for this.
Keep it up. I appreciate the fact that you're sketching your own ideas and executing them rather than regurgitating some other designs that you find online.
RE: Create a logo for the Python package fpl!