Why don't you do a book and print all these ? I would surely be a customer !
Probably because the images are copyright. Using them to share alternate covers among fans is one thing. Using them to publish a book is something else.
And what if an editor would be interested ?
What, in licensing all the artwork used from all the various studios, and getting all the legal clearances and approvals necessary for who's images appear and how the art has been manipulated?
Then, in that case, I'm sure it could happen. Do you know such an editor?