I think that you are looking for some overall advice, and not specific advice on any one of these covers.
My advice is this - look at what others have done. The WIP forum is a great place for this - because you can see some good final resulting covers, but you can also see the progress as it was created. Then, when you are ready for a new creation of your own, work through the WIP forum.
Another idea: look in the downloads area for some templates. They are good for letting you know what belongs where for the different movie companies. There is one mega template out there that I used for the the one cover I created (I'm more of a label guy). But if you go this route - don't be tied to the template, be willing to go out on a limb and change things up.