Darien: You were right about colors, changing a bit the Blue component makes the picture better. I also tried to make the Face less flat. For the texture of an Octopuss, It was just a try, I didn't want to draw a "realistic" Octopuss...
And the datas about the c64 graphic mode interesting, but I don't understand how you draw your art ? You draw directly with a c64 or with a "normal" machine ?