Oh, there's no need to apologize. At no point I felt offended by you.
Or did you mean you now want to "ignore" me and wait for RoosterDragon's input when you said that you haven't changed your mind? ;) Heh, no worries, that's okay, too.
I just regret that I find it difficult to appreciate (or even understand) what you're trying to accomplish here. To me, it looks like you are trying to find an elegant solution to a problem that doesn't really exist, maybe even at the cost of usability. And maybe I'm completely wrong and there's nothing to worry about, but that's why I asked for an explanation in layman's terms, because admittedly, the scripts you posted might as well be in Chinese for me (just for clarification's sake: I don't know any Chinese). All I can do is point to the parts of your descriptions that I feel might
cause problems (however small) and hope that you have either already considered these or know how to deal with them.
And yes, Desktop Ponies' pony editor contains a tool that helps create those .art files. Also, just ask RoosterDragon how often I have pestered him with mini-updates of various character sprites. I'm actually surprised he didn't get sick of them eventually (or if he did, he at least didn't show it). Sure, most of those didn't have transparencies to worry about, but they could have. And if I decide one of those days to give all of the crystallized ponies blinking animations (unlikely at this point, but this is just an example), I'd prefer not having to reassign all of the transparencies all over again. That's the nice thing about .art files: as long as I don't mess with the palette of the sprites, they should still work and I don't have to worry about all of the transparency data being lost just because I made a tiny change to a gif.