From the Vault Series, for the alternate Art.
Duel Decks... Alternate Art and decklists would be great.
Promos: FNM, Judge, Prerelease, and Release Promo cards would be great... perhaps in one same 'set' 'Promo' classification. I know the Promos are weird because the Art is not readily available on the Gatherer, but I could help round up art.
Thanks for all the work that you do for the plugin though Bort. Whether we get this stuff or not, I'm happy with the setup.
I mentioned in this post (http://www.lackeyccg.com/forum/index.php?topic=1112.0) the idea of adding custom card images. This would allow players to add the cards, like those you mention above, as well as any other custom art they wanted without needing to pressure Bort (the guy who runs the MtG plugin) to do so.
With the above addition to Lackey, you could go and find any images you wanted for cards, no matter what release they were from. I'm not sure about if Lackey allows animated .gifs to be used as card images, but it's even possible you could create "foil" images similar to what Magic Online uses.
Yeah I really hope these get implemented at some point.