Hmmm critique! Well, I have to say your illustration is just spot on, the anatomy, colors and direction is just perfect, but it feels like the background and text don't do it justice.
Perhaps take a look at some classic old movie posters to get some ideas? there was a lot of really great graphic design for those old films, I think there's a lot of inspiration to be had there. The best titles are the ones who not only communicate the title, but communicate the idea too. [link]
I really hope to see future versions of this! Nice work.