I can tell at least one more thing from "True Blood" -- that cover reeks of Assumed Male Gaze. To viewers who enjoy ogling objectified female bodies, it will appeal. To viewers who prefer women as active characters, probably not.
I imagine it would also apply to video game covers as well. I notice that books don't have this problem so much, since it's a non-visual medium so the themes/genre are often the first thing displayed rather than the actors. Huh.
Jaka's Story is one of the best graphic novels ever made, flaws and all. Didn't Dave Sim do the whole "I'mma make a 300 chapter comic!" on a dare? I think the whole thing is a fascinating psychological study, right along with "In the Realms of the Unreal".
I'm often thinking about the comic cover I'm gonna make for my graphic novel when my first volume is done. I kind of had a feeling what was important but I could never point my finger on it! Thanks for putting it into actual words, now I can remember it better when I work on the cover!