Hope they don't go with the character posters for the front and back.
I think a mash up of them all or at least the main crew for the inside art would be good.
Theatrical poster for the front.
Then either the teaser poster for the back or even Krall.
Front
[Show spoiler]
Inside
This sort of thing but take of Krall and put in the others
[Show spoiler]
Back
without the "Beyond"
[Show spoiler]