This is awesome! God I need to draw Spiderman. Such a great excuse to draw insane dynamic poses and ripped men.
I did want to ask about how you do linework, tho, given how you included some intermediate stages. How do you go from the sketch to the final thing? Do you just clean up the linework a little, do you totally redo it, or something else? I notice some artists don't use lines at all in the final version, but it looks like you're using them.