(Actually, you may or may not want to remove the trapezoidal "Star Wars" from the bottom of the back cover of both the "Circus" and the "Style A" type covers, as it now reads Star Wars Star Wars Classic Edition, which is a bit redundant. Although it's in line with Empire and looks good.)
Your design works much better with the "Style A" type ANH poster, which is sad as the "Circus" poster is the intended one for Classic Edition. Ah well.
Excellent work.
And yes, perhaps an alternate version could be created with some information about the discs and the edit on the back.
(Perhaps the alternate version of Empire could, just for the hell of it, use the flat [non-tilted, rectangular] version of the Empire logo in place of the trapezoidal Star Wars, just to have a version that says Empire on the front. Although I prefer having it just say Star Wars, that's classy and people already know what movie they're looking at.)
(Another possibility for the ANH Circus poster, although it would be a pain to do, would be to replace the "Star Wars" text up top with the regular non-trapezoidal Star Wars logo in gold, to give it more of a uniform look. Just throwing out ideas for anyone who wants to waste their time in Photoshop.)
Here is the official disc art for Star Wars Classic Edition.
http://orangecow.org/starwars/CEdvdround.jpg