Hey Zera. Thanks for the kind words.
Did you have something in mind? At the moment I'm working on another pet project, so won't likely be returning to this for a little while, but I'm interested in what you were looking for.
As for cards with transparent backgrounds, sadly the way I built some of the cards would mean a lot of work to make that possible. (though the zip does have cards with transparent edges if I recall correctly).
Sorry, I know those might not have been the exact answers you were after, but feel free to let me know what you mean by "environmental" and I can mull it over.
Thanks again. :)