the only other thing I would say is just to keep line weight in mind, like if the lines were thicker on the girl it would push her closer to us and if they were a little thiner on the octopus it would push him back a little more. The transparent bubbles look good. Does that help?
I dig the drawing, especially the octopus dude. I wish the url was smaller and maybe a different font for the bottom type, it kinda competes with the band name. The colors look great. It looks good Beto, did you do the drawing and everything?